You forgot ebay.com. You know, to get a new router.
Seriously though, flakey routers are the cause of constant disconnects assuming you're not being kicked by server for bad behaviour (too often refreshing).
I recommend getting a decent(read: STABLE) router. Better yet, get DD-WRT/Open-WRT and a JTAG cable for replacing firmware. I put a fan in a $30 router and it hasn't crashed yet. However that's overkill for most. I also got the WRT-54GTM which I don't need a fan on, and can mod the firmware. It worked good enough, so I didn't bother modding it. If you have tried everything, and your router turns up being the problem, then get a good model and try again.
http://en.wikipedia....rmware_projects
This again is for people who've exhausted all the other sites and still can't get the router working right with eMule, no matter which computer they try it on. If your ISP is messing with you, no amount of changing routers helps. ;(