See my sig, my PB is constantly low on memory. Last night I had iTunes, Firefox and Dashboard (8 widgets) running and it was out of memory. Other times I'll have just Azureus running and no free physical memory. This seems to be the norm. I find myself constantly restarting my computer to reclaim memory. Do I really need more than 768mb of RAM for day to day stuff like this? I have Windows 2003 servers running quite happily on less memory. I'll buy a 1gb stick if I have to, though its not cheap and would have to try to sell the 512mb I have in there already (which I'm sure I wouldn't get much for). I'd rather wait until Leopard next year to spend more money on my Mac. This is, however, the only complaint I have about a fantastic machine.