Pavel,
I guess to some extent it could depend a bit on where you fish (size of browns, baitfish present) and water conditions (depth, clarity).
But the zoo cougar and sex dungeon and other sculpin type patterns are very good, especially if you're targeting big browns.
My all around favorite is a black marabou muddler. It has a lot of action because of the marabou, even in still water, it pushes a lot of water because of the head, and the black silhouette seems easy to pick out in stained water. Strikes can be so vicious I'm not sure if is taken as food or if it just triggers some deep seated sense of hatred. Fish will sometimes go out of their way to chase and slam them.
It can be fished a number of different ways, including weighted ones on a long leader and floating line. But I usually fish it unweighted on a short leader with a sink tip. If you're in moving water, try both swinging it, and stripping it. If you swing it, you can also let it hang in the current at the end of the swing, the current will pull it up, and this often triggers strikes, and you can also drop it back from upstream steering it into lies in front of rocks, into the head of a pool etc. Everything is worth trying: dead drifting, rising and falling at the end of a line, slow retrieves with short occasional twitches, and rapid retrieve with fast strips (especially along undercut banks).
And don't be afraid to go big. On big water I'll go to size 2, but usually a size 6 seems to be a good fly for most places, especially in deep pools, and/or off colored water. Perhaps a bit smaller for smaller streams or clear water.
In still water or big pools with little current, a good thing to do with a sink tip is cast out and count down to fish different depths before starting a retrieve. It is an excellent fly for SM and LMB too.
Other flies that have worked for me, usually on a floating line are standard muddlers, including mini muddlers as small as size 12 (on clear small freestone streams), and the Shusan Postmaster (an old timey pattern) on slow moving, fertile streams.
Good luck,
Mark