Any kind of dinosaur or animal themed robots would be super fun to me. Maybe a T-rex or Brachiosaurus.
Other robots from Synthiam community

Jeffmorris's Homemade Biped Robot
I built a biped robot but I found out that the servos that came with the EZ-Robot kit are not strong enough. The hip...

Mcjeff0125's Robie Sr, Dr. Theopolis Hybrid
May I present to you my Robie Sr, EZ-Robot mod. As you can see, I did not use the stock Robie head. My main reason was...

Cardboardhacker's 1/2 R2d2 Scratch Build
After watching DJs R2D2 Video endlessly I finally broke... eek I decided to make an R2D2! But after seeing how big and...