Late night eats

....cheap, really late-night dining options in SR area that don't involve words that end in "-enny's"

I don't know if you consider this the SR area, or cheap...but Humble Pie next to the Black Cat in Penngrove is awesome! I think they are open until the bar closes. Not cheap like Denny's, but won't set you back as much as Underwood in Graton (also open late)
The people are really nice too.
http://humblepiepenngrove.googlepages.com/home

Also, there's always Adel's....comparable to Denny's, but a notch above and a bit cooler, somehow.
http://www.yelp.com/biz/adels-restaurant-santa-rosa

Taco trucks on Sebastopol Rd. My favorite is La Texanita.