The important feature to consider in selecting yarn scissors is the length and sharpness of the blades. You'll want short but sharp blades for cutting and trimming yarn ends, especially in ; you'll want a bigger blade yet still sharp for cutting felted projects.
My favorite scissors so far are my classic "stork" or "crane" scissors. They just exude craftiness and evoke a simpler time in stitch work.
I also love my flower scissors because they are just so beautiful (you know how I feel about flowers!), and I bought them on a special trip to London a few years ago.
These little rubber scissors are great because they have a protection rubber cap. I found them in a needlepoint/embroidery shop.
For cheap and easy but effective scissors, you can't go wrong with these "thread nippers" that tuck right into your project bag without worry.
And for travel, nothing beats the "yarn cutter pendant" available on Amazon (affiliate link):
This article by Creativebug gives great scissor options for all fabric and needle craft projects. We'll be covering other tools that you need to have on hand for crochet projects (we've already covered stitch markers here), so please come back for more!