Shoutbox

After that script I had trouble with, the problem was sloved by a typo after like 2 hours so I am a little pissed off atm. Anyway can someone give me a function name for taking a peice of text (like http://reallllllllllllllllllylonglink.com) and change it to (http://reallllllllll...), what function would I use for this? Thanks