Robbie Coltrane?
Just saw The World's End w/out realizing who was in it (besides Simon Pegg). When I saw Pegg's character meet up with Andy, I thought the guy playing him was that guy from Nuns on the Run (Robbie Coltrane). Only later did I realize my mistake. Still, I think Nick and Robbie look a bit alike, despite the differences in their ages. Nick could play a younger version of Robbie, I think. Check these two pics:
http://www.imdb.com/media/rm4030304000/nm0296545?ref_=nmmd_md_nxt
and
http://www.imdb.com/media/rm3002187520/nm0001059?ref_=nmmd_md_pv