Gettin' jiggy wit it...
Over the past few years I've seen a definite resurgence in the use of jig style hooks for tying flies. Once relegated to the bass or jig fishing world where I had to "sneak" my hooks from the bass hook section in stores, these effective hooks are showing up more and more in the line-ups of most fly hook manufacturers these days.
|A jig style crawdad pattern|
As far as tying considerations, you'll need to think a bit upside-down in your tying as the hook will usually be inverted in the vise and you'll need to deal with the hook point on the top. If this becomes too much of a pain, you can also tie the flies "in the round" (similar to the baetis nymph above), where there really is no top or bottom to the pattern.
|Great Stonefly pattern|
|Cheech's Snorkel Hopper|