You won't be (nearly) starting any wars with it, not that it matters -- the raw nostalgia value can't be measured! Unfortunately, you'll need more than a pair of rose-coloured glasses to buy David Lightman's (played by Matthew Broderick) IMSAI 8080 from WarGames, but hey, it's amazing it's for sale at all.
First it might be good to know exactly what you're getting. ITWorld's Phil Johnson took the time to contact owner Todd Fischer, who informed him that along with the computer itself, he still has the keyboard (IMSAI IKB-1) and the modem (Cermetek 212A).
Best of all, the bits all work... as far as Fischer can tell.
If the news sounds a little familiar, the parts actually went to auction at Christie's few years ago -- the going price then was in excess of $US25,000. Fischer, however, wasn't sure the machine would survive a trip from the US to the UK (when Christie's is based) and so didn't go ahead with the sale.