The Usual is a great pattern, and floats like a cork even in fast water. The Snow Shoe Hare Foot (not plain ole rabbit foot) makes great emerger wings too.
Some other alternatives to hackle for dry flies are flies tied with CDC like CDC and Elk Hair Caddis,
Spent wing mayfly spinner patterns tied with CDC or poly that are great for slow water stretches.
Sparkle Duns and Comparaduns (for mayfly imitations) and X Caddis (for caddis) are good in slow to medium fast water. These patterns rely on fine hollow deer hair (sold as comparadun hair) for flotation. A 2 x 2 inch patch of comparadun hair goes for 2.50-3 bucks and will tie about 100 flies. You can get it bleached, or in natural colors in different shades of grayish brown (light, medium, and dark) to match naturals. For real small ones you can use CDC for the wing instead of deer hair.
Craig Mathews' Sparkle Dun
"Comparadun Quill Gordon - #239- FAOL"
X Caddis- this one uses elk, but you can use deer hair too
Fly Tying Patterns for begginers - Copperfly.net - The X-caddis Flishing Fly
Another pattern, invented by Fran Betters, the same guy that invented the Usual, also uses deer hair for both the wing and the tail, and is a great fast water fly where exact imitation isn’t so critical. This is the fly that the Comparadun, Sparkle Dun and X Caddis are based on, but floats better and is easier to see. You can use it in places where you’d throw a Wulff or Humpy.
On The Fly
All these flies actually work, and it's a great way to knock out a lot of different flies for different situations like specific hatches and water types without breaking the bank.