What kind of pen do most people use for pen tricks?

There are special trick pens made for invisible ink, concealed radiOS and other clandestine and/or espionage operations. one used simple red over black inks but needed infra red ( Dark Red) glasses to read the message, this was the Mattel Zero-M spy pen in the late sixties. Cool Toy! If you mean the art of pen spinning, for beginners, use a BIC pen. You can also modify pens or pencils to make them balanced. Try experimenting with different pens to see which one works best for you or maybe you can buy them on eBay? xD