Two of the best things I've seen on deviantART in a while:

(HUBBLE by *dv81)
A collage of Hubble Space Telescope photographs seamlessly threaded together along with digital terrains and planets through a combination of MAXON Cinema 4D, Adobe Photoshop CS2 and Planetside Terragen.

(The Whimsy Cats by `cosmosue)
z/OMG the bestest faery/kitty thing evar! Wonderful, whimsical fantasy piece. (^*^) A bit of Poser 6, Photoshop and use of a Wacom graphics tablet.

I've been squeeing internally over these for the past while, ee.