Rock Climbing Quickdraw (2 carabiner types)
A stuffed toy rock-climbing quickdraw, first invented when friends of mine (both climbers) had their first child. The toy is made in three pieces - two carabiners (one straight gate and one bent gate of course) and a sewn sling to hold them together.
A good way to use up some scrap yarn in any size. (If you use something other than worsted weight, be sure to use a needle size one or two US sizes smaller than is normally called for for that size yarn. This is commonly done when making amigurumi so that the stitches are small and tight, to prevent the stuffing from leaking through.)
November 30, 2014: added a PDF that actually works!