If you want to stretch out your current system adding memory will help, if you can get up to 1gb total you should see a noticeable difference. I won't build or spec anything for myself with less than 2gb currently.

Upgrading to the new core duo or core duo 2 systems will be a nice leap but again if you want something that will last you save a bit then go for it.

You might also just need to clean up your laptop and it may be just fine for you again. scan it for spyware, viruses and DEFRAG!! I can't tell you how many times a simple defragment makes a world of difference for people.

If you have questions on any of the specific suggestions let us know, I'm sure some folks will jump in here with their suggestions as to which programs and such they like. I have some I like as well...a big part of my job is keeping end users up and running as efficiently as possible.

Here is a great resource for info on notebooks: www.notebookforums.com

(I think I can post that I have in the past and I am not affiliated with the site other than being a member, and it also has nothing to do with reptiles )