Get flash to fully experience Pearltrees
Luz is a music visualization studio for VJs and creative couch potatoes. It’s free and open source. Luz can use any combination of Wiimotes, Wacom Tablets, MIDI keyboards and sliders/knobs, gamepads and joysticks, and laptop touchpads (as X/Y pads) to create any sort of interactive visual toy you want. Hand the devices to your friends, attach them to music instruments, gather around the screen (or projector!) and jam.
If you want to merge pdf files in Mac OS X, try this freeware – CombinePDFs. I’ve tried to merge 20 pdf files into 1 without any problem. It’s fast, easy and Free.