Good lord! FF consuming 80MB of ram? That is something fierce. What plug-ins are you running?
To the original question. Buy an IBM T series. I have a T40 at work and have had it for almost 2 years. This thing is awesome. I lug it to meeting after meeting to the house etc and have never had a problem even after beating it to hell. I bought a T42 for school off of EBAY a couple of months ago and I love it! I found it cheaper on ebay than IBM employee purchase price(it was new in box as well). Plus I got a 3 year warranty and no taxes!I payed $1400 for it. One diff between T and R series is what they are made of. The R is plastic and the T is magnesium which is lighter and more durable.I have 512 of ram and that suits me fine. I really can't tell the different between my work T40 1.3g 512 and personal 1.7g 512. I have yet to really slow down my work one either and that is running oracle, access, about 5 excel files a few explorer windows and lotus notes if this won't slow it down I can't imagine anything you would need in law school will slow it down. 512 of ram should be plenty.