A lot of folks ask me about what sort of "Grickle" objects exist out there for gift ideas. Here's a list of links to things you can get for that Grickle person in your life:
Puzzle Agent video game series
http://store.steampowered.com/app/31270/ (Puzzle Agent)
http://store.steampowered.com/app/94590/ (Puzzle Agent 2)
Exclusive prints and music from the Grickle store (Hidden People set, Children of the Night & their Dad set, Principal Skeleton, Space Sadness)
Gallery Nucleus special prints
The Book of Grickle from Dark Horse Comics
Hope that helps out this holiday season!