AC has posted a fantastic article today. He talks about the hardware he uses for SharePoint 2010 development. Here is the link:

http://www.andrewconnell.com/blog/archive/2009/11/03/doing-sharepoint-2010-development-ndash-whatrsquos-in-your-rig.aspx

Article has some fine suggestions about the hardware that you can use and increase your development speed. These are not mandatory requirements by the way. You can use a low configuration laptop to do SharePoint 2010 development but that’s the primary difference between a novice and an expert. If you just want to experience SharePoint 2010 (no development), you can run it on a 32 bit system as well using virtualization. One of my SharePoint 2010 installations run on a 32 bit system. Following is the configuration I use for 32 bit system:

Lenovo T61 (IBM ThinkPad)
OS: Vista 32 bit
Processor: Intel Core 2 Duo T7700 @2.40 GHz 2.40 GHz
RAM: 4 GB (32 bit systems use only 3 GB)
HDD: 160 GB Single Partition

Virtualization:
VMWare Workstation 7
Windows Server 2008 R2

This is the minimum configuration I believe that you need to run SharePoint 2010 . You can increase the performance by adding a SSD (as suggested by AC) and/or increasing the RAM. For my daily use, I use a 64 bit system for SharePoint development. My 64 bit configuration is as following:

HP laptop
7200 RPM HDD
8 GB RAM
Quad Core Processor