We made some example prints with the purpose of showing how they could include moving and interlocking parts. This heart keychain with rotating gears was done as a single print (all as one object) in PLA on our Ultimaker 2+.
Link to the thing file by UrbanAtWork
If you want to see and feel how this print or any others we’ve made looks in person all of these examples are available to play with and are located on the shelves just opposite of the ProtoLab.