The 3DS is Nintendo's latest handheld console, the successor to the DS and DSi. It is not currently (2011-03-21) out in the US. However, I picked one up on a recent business trip to Japan and have been having a lot of fun with it :)
Size-wise, it's comparable to a Game Boy Pocket.
Here is a Nintendo 3DS cross-eye 3D image gallery, for your viewing pleasure.
The images in the above gallery were generated by cr3ds, the Nintendo 3DS MPO processor. It extracts left and right images from 3DS MPO files and can generate cross eye 3D images.
Check it out, I included an example MPO file on the project web site in case you don't have a 3DS of your own to play with yet.