I have to procure laptops at work. The main thing that I look for is a good high quality resolution. Problem is that you have top balance this against cost. The R51 1829 was the one for me. It has now seen end of life as we know it, replaced by an R52 version.
To start with the R51 cost around £1100 to but. With your money you get the following
Pentium M: 1.8GHz
512MB RAM (with spare slot for expansion)
Built in Bluetooth, wireless and firewire
The resolution at 1450 *1028 is not half bad at all. You can get the best applications up on he screen without having to scroll around to find what your looking for.
The Pentium M 1.8 may not be the fastest but combined with the other components it is more than quick for those business applications.
512MB of RAM come as standard, any less than this and you are wasting your time. I always upgrade to 1GB. This is very easy to do even for the home user. There seems to be this scary though with home laptop users as to breaking and damaging them. You can slip of the RAM slot cover, plug in the extra module and of you go. With 1GB the R51 flies.
The 128MB graphics card is over qualified to provide a good clear quality picture when working. Whilst you gamers may not think its of any use, you can still play with the best of them. At the end of the day laptops are laptops, meant for a purpose, games should be played on a desktop if you are serious.
The R51 comes with a number of quick access buttons along the top to allow you to turn on Bluetooth, wireless etc at the touch of a button. This does make life easier and means you don't have to hunt around in the Start Menu to enable equipment.
USB ports are standard along with a good quality DVD writer.
I have to question the design of the IBM. Whilst it is strong and durable it never seems to develop or improve. It reminds me of an old T21 I had a number of years ago, may be a little thinner but exactly the same otherwise. Still, why change what obviously works .
Software wise you get Windows XP Pro, Pro being a must for a business user. You also get the IBM software bundle pre installed. In my book this is a bad thing. The more tools and utilities you leave on a laptop means the more chance you have of a user being able to crash it. The R51 is no exception here. I have come across multiple problems with the IBM connect wireless utility becoming corrupted whilst working along side the XP utility. Best way to get around this is to remove it altogether and let windows manage everything.
My only other gripe here is the fact that you no longer get a windows CD with the unit. Everything is preinstalled in a secure area of the hard drive. However, doing this does not leave you with much and does leave you creating CD's as emergency backup (loads of CD's)
In general though the R51 is a great piece of kit. You get everything you need at good price.
Have had a couple of keyboard buttons pop off but easily fixed and due to hard users.