Just found the Roku channel...there's not much just yet (as Tim said, the channel just went up a few weeks ago), but I found Fridays, the sketch comedy series from the early-80s. It's apparently Shout's "Best Of" compilation, so hopefully the episodes won't be as horribly edited as Netflix's SNL collection.
Would love to see the WKRP and Barney Miller sets on this channel eventually.