dropdown option before posting

[F0xy]

guys im looking to add a dropdown option where if you are making a post and it includes links to rapidshare and one of the options to pick would be [RS.com] so when you make the post the thread title would be

[RS.com] name of thread

i hope this makes sense and ive added a pick where the dropdown menu would be



once you pick the dropdown bar this is what it would look like when posted