I have three netbooks...
Acer Aspire One - got in in fall of 08 with a version of linux (linpus lite --> derived from Fedora 8 I believe), 8GB SSHD, 512 Ram, 3 Cell battery, Atom... good for me at the time just needed a word processor and web browser. But I lost Linpus for some reason due to a 'HAL' error and now its been through about 4 different OS's (xp, kbuntu/xbuntu, moblin and a few others)
Eee901 - 16GBSSHD, 6 Cell, 1GB - now its a parts computer for the other two (Acer currently has 1.5GB ram and is awaiting the Android OS...) Good for the money, but really slow, get the regular hard drive and as much ram as possible
Eee1001 - can't remember the specs but its leaps and bounds better than the 901, came with much more ram and a better processor, currently able to dual boot OSX Leopard and xP this is our primary laptop, good all round computer but it does cost slightly more than the base model acer, get what you pay for - battery lasts decent amount if you put it in power saving modes