I can't believe how cheap RAM is right now. I was online shopping for a gift for my Dad and came across 4GBs of PQI DDR2 PC2 5400 RAM for $92.99. That's a pretty good way to cheaply upgrade a Development Workstation or Server.
Just 5 months ago I paid $120 for 1GB of DDR 500 (PC 4000) RAM to upgrade my Desktop box to 2GBs. I know I paid more for that RAM because I had to match the older, high performance RAM I already had in my system, but I just can't believe you can get 4GBs of RAM for under a $100.
I remember paying almost $400 dollar to get 16MBs of RAM in my old 486 PC (it was four, 4MB SIMM sticks.) That was at a time when 16MBs of RAM was a huge amount of RAM and DOS and Windows for Workgroups still ruled the PC world. I eventually jammed all that RAM into a Promise EIDE Caching Controller card as RAM got cheaper and I needed more RAM for Windows 95.
If you're looking for a cheap way to upgrade the performance on your computer, you might think about buying some RAM now. If you use VMs or have a Development Server where you have lots of services running (like SQL Server and multiple versions of ColdFusion,) adding RAM can really help your performance.