WRT54G repeater bridge
UPDATE: As of October 17, 2015, I can no longer recommend running your WRT54G as a repeater bridge. It fails just as often as when I was using it for a NAT router (i.e. at least daily). Get some new hardware folks!
So, I decommissioned our WRT54Gv5.x about a year ago and replaced it with a pfSense box, a Cisco wireless card, and a netgear switch. I love my pfSense box.
Unlike the WRT54G running DDWRT, the new pfSense box doesn't need to be restarted every day. In fact, it has a 152 day uptime at the moment. Actually, the pfSense machine isn't a new box at all, its an old PC that wasn't being used. Because the pfSense machine is an old PC, I have 64 times more ram than our old WRT54G, hundreds of GBs of space for logs, and plenty of processing power. I'm planning on building a new router machine that uses less power, and actually has gigabit ethernet, but for now almost everything working really well.
The one issue that I'm facing is that the wireless card that I bought doesn't have much of a range. Without the WRT54G, I don't have dual antennas that are easy to point in different directions. I looked into some ubiquity devices but I'd rather not spend any money extending my wireless network until my router is rebuilt.
So, I just temporarily brought back the WRT54G as a wireless repeater bridge. It seems to be working pretty well so far (for last hour). I now have a great wireless signal all around the house. The best part is that it was free! If you no longer have your WRT54G, no worries, get them from you nearest ebay/craigslist seller for about 5 bucks!