A collection of fun science experiments at Bizarre Stuff. Includes the Sparking Grapes (with formulas), dancing raisins, match stick rockets, making fake blood or glass, and The Big Page of Slime. There's also a slick trick with extracting colors from a black marker.
I found them while searching for invisible ink techniques. Believe it or not you can get invisible ink for your inkjet printer. The coolest has to be the black light invisible ink. Some places call it UV ink and it's featured on lots of security sites for marking valuables. Also used for concerts and bars, where they mark your hand such that you can't see it without the special light. I was thinking about using it for construction. While installing a closet organizer the instructions had me marking up the whole back wall with a pencil, which is a mess to erase afterwards. What if I used a UV marking pen instead? Simply plug in a black light bulb or use some fancy Ultraviolet LED based flashlight when it comes time for drilling or nailing. No cleanup required!