So for example projects that deal with video streaming and its intricacies, scaling or optimization, or my personal favourite, maintaining or porting legacy or broken systems done by programmers that are worth $5/hr.(sorry, i don't mean to be harsh, but we've all been there)
Typically those kinds of projects are not easy to come by and are not that many to begin with. They also tend to be awarded to people you've already worked with or know, not auctioned off on sites like elance.
I've once worked on a video streaming solution that used elements from Red5 and it was known that good Red5 consultants won't talk to you for less than $100/hr. I was not making anywhere near that of course, but I use it as an example.
You may want to divide your price per hour by 4 assuming they work an average of 40 hours per week