Two serial port infrared (not irDA) based remote controls. These two products have been around for several years and you have many free software for Windows and Linux that people utilize to remote control their computers. The Creative Remote is credit card sized. The Packard Bell Remote is a bit more bulky but has more buttons for those that want the extra buttons.
Most TV remotes will work also work with these infrared (not irDA) receivers assuming the infrared signal sent from the remote is consistent and repeatable. (Some TV remotes send unrepeatable signals or cycle through multiple signals). For a list of TV Remotes already “programmed” check out LIRC