If I'm just tying for the sake of tying (i.e. the Cubs suck, there's no sports on and it's 95 decrease with 100% humidity like last weekend), I'll tie a mayfly dry - kind of a Proper Perfect Dun.

The Pefect dun was a catskill type of fly but with the dubbing crossing through the underside of the collar in an X to split the bottome of the collar hackle in half (kind of like cutting the bottom of the hackle to create a Lawson-type of Thorax fly). I like Wonder Wings rather than hackle tips, though.

Dick Talleur's Cut Wing Thorax is similar.