As above really, the install was on the "emerge system" stage about a couple of hours in when my dad thought it would be good to trip the main fuse panel out...
I've rebooted the system using the live cd, remounted the filesystems and chrooted to /bin/bash..
When I did "emerge system" again it told me that everything was up to date apart from 3 config files, but it was still in the middle of downloading and compiling things when the power went..
What now? Redo the bootstrap and try to emerge system again, or flatten the lot and start again?