Well, the memory in my computers, anyway. I noticed my newer deskside computer seemed a bit sluggish running big progams like Microsoft Visual Studio 2008 under Windows XP Pro when I thought to check on how much RAM it had. When my son and I built it in 2002 we installed one stick of 512 MB DDR (PC2100). That just wasn't enough for the load I was putting on it, Task Manager showed I was trying to use about 600 MB. Oops, the OS was having to swap memory in and out.
So I checked the specs on my Giga-Byte GA-7VRXP motherboard and ordered two Kingston KVR333 (PC2700) 512 MB DDR DIMMs from newegg.com. Slightly faster memory and twice as much of it, whoo-hoo! Also kudos to Giga-Byte's support website: when the motherboard didn't recognize half the memory on the first try, they answered my e-mail question within a couple hours, providing some helpful hints -- turned out I just hadn't fully seated one of the DIMMs).
But that's not all; I took the 512 MB PC2100 DIMM that came out of the home built machine and put it into my slightly older Micron computer (it also has a Giga-Byte motherboard, a GA-7DX Rev 2.2). It previously had 384 MB and also runs XP Pro, so it could sure use a boost. It only has two memory slots, previously a 256 MB PC1600 and a 128 MB 200MHz PC1600. So I moved the 256 over and put in the 512 and voila, 768 MB -- I assume this all ends up running at the PC1600 speed, but still, I doubled the amount of memory in both my home computers, and the memory speed in one of them, for about $46, including shipping. (The home built machine still has an empty memory slot, I probably should have gotten another 512 MB stick. Hmmm. Also, if somebody needs that 128 MB DIMM, I'd part with it for a couple dollars, plus shipping) Now if I can resurrect the screen on the HP laptop that my son just handed down to me, we'll really be in business!