here's one of my favourite songs to see live:
http://www.youtube.com/watch?feature=player_detailpage&v=44DhebIMgAA#t=27 2s
Disappears - Radiation (with Steve)
It's a Suicide cover
And here's Low joined by Ida and RGC's drummer Eric Pollard doing Shots And Ladders
http://www.youtube.com/watch?v=cnakosq5Y4U
(crappy low quality video though)