Open source software for Linksys WRT54* routers

[yeah-right-6yPSQP5VWP/P/9WndSeKLsJ8OCA1ciLf at public.gmane.org (Bill Horne)]

At long last, I have obtained a version of the Linksys WRT54GS which 
will accept new firmware. Before I select which version to use, I'll
ask the groups opinion as to which version will best accomplish the 
goal I have.

I am going to use this as an external wireless client: in other 
words, it will be used to connect a machine that has only wired 
Ethernet to a WiFi hotspot, just as if it were a wireless PCI card.

With that in mind, please pass along your recommendations as to 
which open-source firmware you feel is best for that job. Additional
suggestions are, of course, welcome.

I've heard of Tomato, DD-WRT, OpenWRT, and one or two others. 
Which one is best?

Thanks in advance.

Bill Horne