I recently got a WRT54G v3 (an older version of a Linksys router) off of ebay. I specifically got a version 3 because it's the best router known to man that's under $300. If you can get one for less than $50, my advice is to take it. Up until a few days ago, it was running the stock Linksys firmware. It's not terrible but it's not very extravagant either. We had a power outage and after that, wireless stopped working. I tried many things, including slapping the unit with my balls to make sure this wasn't some sort of misguided power struggle. Putting it back in its place should fix that. No luck.
I had heard many, many times about the dd-wrt firmware. One of the good things about the WRT53Gv3 is that you can install just about any custom firmware you want onto it. I'd also heard in the past about a firmware called Tomato. It's supposedly light, lean, fast, and has great QoS (although I never even bother with QoS).
I decided to give it a shot. I'm in love. It gives you all the options you need for the things you'd want, but doesn't bloat up the interface with extra junk. It's simply amazing. I really think Linksys should just stop bothering to make their own shitty firmware and just install Tomato on their routers.
Unfortunately, Tomato didn't fix the wireless problem, so I had to plug in an old nemesis Netgear router I had laying around. It starting, in memory of times past, dropping my connection every 5 minutes. Fine for browsing the interweb, but not for streaming music or "videos." I decided to give the Linksys one more shot...and it worked! Thank god. The best router ever with the best firmware I've seen so far, NOW with wireless. It must have been some strange hardware issue that fixed itself.
To be fair, I've never used dd-wrt and therefor can't give a good comparison between it and Tomato. If I had a few extra routers laying around, I'd try it out...but each firmware flash is a dance with the devil and I can't afford to get / find another one.