Got a good list covered there,
Black Books, IT Crowd, Spaced & Peep Show, & Mitchell & Webb Look
I actually haven't heard of snuff box...
Struggling to think of more buttt,
Green Wing which is a really good, one of my favourites and I highly reccomend (set in a hosptial, but think opposite of scrubs, got fran from black books in it)
Brass Eye Which was hilarious, it's a Satire Comedy with someone you may recognise from the IT Crowd.
http://www.youtube.com/watch?v=IlEcGHxfltEIs it Bill Bailey? was a short run show but had some good music comedy in it and sketches, can get it on youtube.
Big Train was a Pretty funny sketch show with Simon Pegg
Hippies was another Simon Pegg Comedy which I never actually saw but the only person I met that saw it said it was good lol.
Then theres some older ones that some find hilarious, others don't
I'm Alan Partridge with Steeve Coogan in it
The League of Gentleman was a sorta weird horror comedy thing
Father Ted about priests in Ireland
The Fast Show was quite funny as far as I remember it (from the 90's so a while ago for me to remember)
Then theres too sketch shows I never watch called smack the pony and drop the dead donkey, you'd just have to take a risk with them lol although I think they were popular at the time.
Other than that I can't think of any off the top of my head unless I go back to the 80's or the smaller obscure ones that were either weird (Jam) or that I didn't watch but have just heard of and or watched and not gone for them.