The Squidward Light-Up Pen Pal is a toy that was sold in Burger King kids' meals during October 2011. The toy was a pen in the shape of the Squidward character, with a point at the end that lit up. It was sold with three activity cards (a tic-tac-toe game, a maze, and a spot-the-difference game).
The toy's description from Burger King's no-longer-running Club BK website:
"Flip the switch to light up your Squidward Pen! It comes with three activity cards, too!"