Earlier this winter I noticed tons of midges on the bottom of the rocks on my local spring stream, the Donegal. I decided to tie my own midge and I put together my own version of the brassie, using red copper wire, peacock hurl and three little pieces of crystal flash. The red was a choice to serve as an attractant, same with the crystal flash--while it simulates the breathing tubes, its also sparkly. The solid copper wire body gives the midge a bit of weight without a bead head. I used size 16 Eagle's Claw nymph/scud hooks since that was all I had handy and frankly its harder for me to tie smaller flies.
It's been a killer pattern for me this winter on several streams. Two weeks ago my brother-in-law and I hit a new spot for us, and ran a rig with a beadhead flashback pheasant tail and the midge as a dropper. I kept nailing brown trout after brown trout on the midge--never on the pheasant tail. Most were 12-14" long but I caught one nice 16" fish. The native brookies in the same stream were all biting only the pheasant tail, even though it was a larger fly (14) and they were smaller fish--6-8" average. My brother-in-law finally switched to the midge and had similar success. I suspect any nice midge pattern would have worked, but it was interesting how specific the fish were in terms of what they wanted to eat.
Oh, and knowing you have a bite is much harder with those tiny midges. The slightest dip of the indicator might be all the notice you'd get. I missed many sets and many bites, and I'm sure some of what I thought was the fly bumping the bottom was actually fish sipping on the midge and spitting it out. They just don't take a midge aggressively, and in the winter that's enhanced since they're just slower in general. Still, there's nothing like seeing a nice big brown with a tiny midge in the lip, in your net.
Jeff