There are no shortage of USB missile launchers, such as the Spyfire R/C Blaster, Wireless USB Missile Launcher, and USB Missile Launcher with Webcam. However, the USB Thunder Missile Launcher has them beat with impressive range and accuracy.
The USB Thunder Missile Launcher can rotate 360 degrees and has a range of about 45 degrees up and down. It shoots very fast, to a distance of up to 25 feet. This gives you plenty of range to strike any corner of your office, or to rain foam down on neighboring cubicles.
Control is easy, using the mouse or keyboard, and you can optionally use the sound effects to hear the missile launching when you fire. Currently the software is Windows only (Windows 7 / Vista / XP SP2), but they promise a Mac version soon. It comes with 4 foam missiles and an instruction manual. Its size is approximately 12.8 cm x 9 cm x 9 cm.