They look like this
http://media.rei.com/media/zz/6452beaa-2119-4cc7-a6bd-d5658288dc4c.jpg

I finally discovered the actual name for these is 'side release buckle'.

Now, with the obvious exception of marckees and brusmas of the forum, I'm guessing you guys, like me, have used these things frequently and never really known what their technical name is.

What other things do we use frequently without having a name for?