Since 2000 I have been using Allplan FT by Nemetschek.

In the 7 years I have been using the package I have never regretted the investment - it is a powerful and comprehensive architectural solution for both 2D and 3D work.

However the Nemetschek acquisition of Graphisoft and thus Archicad, has unsettled me and maybe it is time to look at the 3D cad market.
I ran demos of Revit, Archicad and VectorWorks to see what they had to offer and the most promising of these is Revit. I now have a licence of Revit Architecture 2008 and have done the basic training course. Once I have run through a real project (May 2007) I will have a better idea of its abilities.

For more on Allplan FT see Allplan User's pages

I should also mention Trial Systems Ltd.  I have used their Drawing Express pen and tablet based cad system for 14 years and they provide some of the best software support in the UK.

'Drawing' with a mouse is bad news for your hands. Wacom tablets offer an excellent alternative and are widely used in graphics studios. Tablets were once common for AEC cad systems but have dwindled due to their expense, (with the exception of Trial Systems Ltd who supply an A3 Wacom tablet and cordless pen with their Drawing Express software) despite concern over the increase in Repetitive Strain Injury (RSI) among office computer users.

IMHO the best interface device to appear on the graphics/cad market for many years has been the Cintiq 21ux tablet/screen from Wacom.
<< Click for larger version (241Kb)
Despite the $$$$ cost, a huge success around the world.

I bought mine from ChauDigital in London - great customer service.

<< Click for link to page with larger version
Here is a (very old) picture of my office with 2 Cintiqs - the new 21ux and the older 18sx - the linked picture shows the latest 21ux and the original 21ux...

Autodesk the developer of Autocad introduced the 'DXF' file format many years ago as a way for different CAD programmes to share drawings - i.e. a CAD programme saves drawings in a format that is unique to itself. In order to give that drawing to say, an Engineer running a different CAD package it must first be 'exported' or 'saved as' a 'DXF' format file. In fact DXF files are merely text files which is why they work (it also makes them large). Unfortunately Autodesk have 'enhanced' the DXF format over the years (along with the native 'DWG' Autocad format) leading to compatibility problems if you do not keep updating your CAD software. A recent development is the emergence of the 'OpenDWG Alliance'. Check if your CAD software producer is listed at their site www.opendwg.org as it costs money to join but should guarantee long term Autocad compatibility being available to your package.

IFC and XML promise 3D data interchange between systems but in reality this is limited at present.

A point to watch if you are trying to email a DXF file - your email programme (Outlook Express or whatever) may see the file as text (which of course it is - see previous paragraph) and simply insert it into the body of the email when you try to 'attach' it.
There have been reports of corruption to drawing files of any sort when emailed. The solution to both problems is to 'zip' the files first which also makes them smaller and quicker to send. (Winzip is a shareware compression programme which runs under Windows. There is a DOS version called Pkzip as well - and a Mac programme called 'stuffit' which does the same thing).

The cause of more 'banging-your-head-against-the-wall' than almost any other aspect of CAD.

After years of using Hewlett Packard cad plotters I changed this year [2005] to the new Canon 6400 plotter - outstanding high resolution output at reasonable cost.

Modern plotters tend to connect to the parallel port on the back of the PC or a USB port. This is easy and fast to set up. In prehistoric times (over 10 years ago) serial interfaces had to be configured by the CAD equivalent of a witch doctor! Larger, newer plotters sometimes have built-in networking otherwise you can buy a network interface.
Alternatively if you have a spare PC lying around hook it up to the network as a print server.

If you think of how often you tend to print out an A4 page from your desktop printer when word processing and find a mistake and then print the sheet again the same thing happens with CAD drawings. The paperless office is a long way off.

I do all my copies on the plotter as you can just punch in the number of copies - not as fast as a large format photocopier but much better line quality. You can only do this with roll feed plotters. Cut sheet fed plotters are a bit of a pain.

It is worth the extra for coated paper in an inkjet plotter. You will find that you make use of the colour abilities quite quickly for presentation. Even the most basic coated paper is a big improvement on the 'opaque bond' photocopy quality paper.

Never use substitute inkjet refills on your plotter - it gives Canon, HP or whoever an excuse to invalidate your on-site maintenance warranty. Note that in most plotters there are 4 cartridges of ink. Cyan, Magenta, Yellow and Black - known as CMYK (yes, I know Black starts with 'B'). Note also that the cartridges -yellow in particular - are prone to clogging up if not used regularly (run a config plot part way every morning if possible). HP say you should throw them away if this happens. With what they cost not likely! I find that a gentle dab with a damp kitchen towel will revive all but the most clogged up print heads on the cartridges. Do not bother looking for the holes where the ink comes out by the way - they are microscopic. An HP Engineer told me that cheaper inks really can cause problems - apparently the electrical resistance of the ink is important and the circuitry in the cartridge holder can burn out with some cheaper inks.

I feel it is worth the money to have a 'proper' A1 plotter. Although much cheaper, A3 and A2 inkjet printers are not really designed as plotters (whatever the manufacturers say). Some Architects maintain that small drawings are easy to file and duplicate but ask most contractors and usually they prefer 'proper plans' where you can easily cross reference plan, elevation and sections with notes - certainly on 'small' works - on large projects I can see some advantage to smaller format output - say for binding details into a book. You can get colour laser plotter/printers at A3 for $$$$.

Note that you cannot easily get true A1 wide roll feed plotter paper. It is nearly always 24" wide because that's what the Americans use and it is only a few millimetres wider. Strangely most people still set their paper size to A1 when plotting on this paper (me included!). At present the 1000 series HP plotters only come in 48" (A0) size - which is partly why they are so fast - the A1 sheet comes out sideways instead of longways.

Watch out for the new higher resolution plotters. More dots means more memory and slower output. Make sure the plotter has sufficient memory or even a built in Hard Disk drive to cope with the type of drawings you produce. You can make the computer's own memory and Hard Disk drive do the donkey work here (there is an option in the Printer Properties in MS Windows) but plotting is even slower that way. The latest HP plotter drivers make this latter option hard to find by the way - they always want to sell you more memory.
The Canon 6400 rasterises everything in the host computer anyway as far as I can tell and so it isn't an issue.

Talking of resolution don't pay too much attention to quoted resolutions for plotters - a 'real' resolution of 600 x 600 in mono and 300 x 300 in colour produces very good results and is fairly quick. Many HP plotters can also output in monochrome in draft mode which is quite acceptable and very fast (set the Draft output option in the Windows printer driver properties - set the colour option to Grayscale if there are coloured fills on the drawing or it will revert to normal printing Update Feb 2002 - this no longer applies to HP500 and 800 - they output same speed in draft colour as mono). Note that I find it safer to leave the default paper type alone - at least for plotting. Changing the paper type can affect the printed output - not always in the way you would expect.