Works for pastebin.com, but not dpaste.com, sprunge.us, ix.io, fpaste.org, ideone.com, paste.fedoraproject.org, hastebin.com, termbin.com, paste.debian.net, gist.github.com, bpaste.net, lpaste.net, pastee.com, irccloud.com, codepad.org or susepaste.org.
I currently have ~40 lines of regex for this, plus some custom logic for a few that don't have raw URLs at all. A service would be very convenient.