Got tired of having all those swap files in the current dir and having them sync over Dropbox or show up in git tracking GUI windows and things

.vimrc

" … blah …

" WARNING:  There are probably security problems with using /tmp/ for this!!! \o/
"           If this directory isn't owned by the current user and not world writable,
"           it's highly likely nefarious evildoers could elite haxx into your vim
"           memories through the swap files. (… project for later …)

" (:-2 to remove end of line)
" &g:directory is the global option directory
" let &g:directory="poo" is roughly equiv to set dir=poo
let &g:directory='/tmp/vim-swap.' . system('id -u')[:-2] . "," . $HOME . "/.swap-vim"
for dir in split(&g:directory, ",")
    if isdirectory(dir) == 0
        :exec "silent !mkdir -p " . dir
    endif
endfor

" … blah …