I was in a similar position a few months ago. I settled on a Netgear WNDR3700 for the following reasons:

* cheap - $79 refurbed @ TigerDirect - http://www.tigerdirect.com/applications/SearchTools/item-det...;

* gigabit ports

* lots of ram - 64MB

* lots of flash - 8MB

* expandability - USB for more storage

* 80211.N support with 2.4GHz and 5Ghz bands

* popularity - well supported by OpenWRT (I'm a former DD-WRT'er and like OpenWRT so much more)

So far extremely stable running OpenWRT trunk and a lot of fun to tinker with :-)