Gnucleus is completely free/non-profit/open-source/you-don't-have-to-give-them-your-first-born-son and is years in development - http://www.gnucleus.net

(and if the lack of ads in Gnucleus upsets you, you can get Morpheus which is Gnucleus with added spyware and ads)

Also since LimeWire is open sourced you can:

Get the source off their cvs server and compile it yourself.

Or (since your lazy) you can grab an ad-free LimeWire mod:

there is Clean LimeWire (which you'll have trouble finding - word on the street is that their servers were flooded so that they couldn't afford hosting)

there is FreeWire - http://www.freewirep2p.com

and there is AquaLime with the funky colors - http://MamiyaOtaru.mangatoanime.com