I use vim a lot, and I use it even more now since my work uses it as well. One thing my boss really loves, and I kinda hate, is an 80 character line limit. I used to just commit style breaking code, but now I can have vim yell at me when lines are too long, thanks to this useful post over at Stack Overflow.
Just add the following to your ~/.vimrc and you're good to go.
" Highlights long lines
highlight OverLength ctermbg=red ctermfg=white guibg=#592929
match OverLength /\%80v.+/