I often have a ton of tests open in one buffer. They're usually related to something I'm refactoring:
vim $(ack -l --perl 'api/v1/episode' t/)
So it's handy to be able to execute all tests in my current vim buffers. Now I can just type
let i = 1
let tests = ''
while (i <= bufnr("$"))
let filename = bufname(i)
if match(filename, '\.t$') > -1
let tests = tests . ' "' . filename . '"'
let i = i+1
echo "No tests found in buffers"
execute ':!prove ' . tests