The Harmony line of remotes and remote items grows a little today with the announcement of the
Harmony IR Extender System. For $59.99, you get two blasters and a transmitter/receiver that allows you to hide your components and use these extenders to control them. An RF signal is transmitted to the blasters which in turn repeat the instructions in IR to the component.
Now, it says on the website that it's compatible with many IR remotes so it doesn't seem like you'll need a Harmony remote to use one of these things. I know for those that love to keep a clean setup, these are nice to have. Also, each one can control multiple devices so if you line one up with more than one component in line of sight, you'll be able to control them all with one blaster.