Pixel King makes a wireless trigger system that supports high speed sync. I can't tell if the quality of this trigger is any good, but I have used other Pixel King products and have been very happy.
The Cactus V5 system uses a tranceiver, however it's highest sync speed is 1/1000. I can't comment on their quality either since I haven't used them, but they tend to get pretty good reviews on the more reputible photog websites.
Both of these systems cost much less than the RadioPoppers or Pocket Wizards.