With Christmas looming, What shows are to having Christmas Specials this year on the respective channels, this includes panel shows and one-offs. AT the moment only Extras series finale amd To The Manor Born come to mind.
Christmas Comedy
Extras
To The Manor Reborn
My Family
Not Going Out
After You've Gone
Catherine Tate
I'm sure that there are more which I'm forgetting. Mark will enlighten us further.
I will, as last, be posting a full rundown day-by-day of this Christmas/New Year season's comedy chedule. 
TV Burp is another.
Peep Show is not the sort of show for films, spin-offs etc. but I think a christmas episode to finish off the series would be perfect. It would star Jez, Mark and Super Hans having X-mas at Jez's mums place. C'mon, I can just imagine David Mitchell sat in the christmas hat reading out a crap joke.