I enjoyed Black Books (and Run, Fat Boy, run) - my favourite episode is "Grapes of Wrath" (1.3) My family still paraphrases the "everything's so very *dirty*" and "not these over here...just these over there" wine bottle mixup. And the "none of this..." rant from the second episode.
I've just started watching "the IT crowd" (also by Graham Linehan) which has similar characters (crazy Irish bloke, nice but odd guy, woman who's more normal but not as much as she thinks she is).