Deleting from Inbox?

I make a lot of friends and sometimes they say ridiculous things they'd probably said while they were drunk. Anyway. I also have messages from people I don't even like anymore. Either I am ridiculous or we need to be able to clear our inboxes. This is important! To clarify not individual messages from one person but the whole thread in one click. It's kind of tedious clicking each message.

I hardly message anybody in here, but I can see this being a problem for many who do. I think that's a pretty good idea.