I will be giving a 3D printing demo at a http://geekthelibrary.org/ event tomorrow, and I need some recommend prints for the demonstration? A few impressive prints with <20 min print time. Any ideas?
Companion cubes are popular. Many iterations on Thingiverse…
I like to find whimsical thematic or seasonal things to print. For a “Geek the Library” event, perhaps some bookmark designs would work?
The whistle. Always impresses.
Yeah, but you’re supposed to be quiet in the library! 
Whistle for all. There is also a mindcraft tournament going on so creeper are appropriate. Creeper whistle anyone’?
Ultrasonic whistle?
RichRap’s 25% rendition of Nophead’s Heart Shaped Box looks cool and timely. Print enough for your crowd, and you might get an encore.
lol ultrasonic whistle.
“Fhhhhhhh!! No really, it totally works! Trust me!”
http://www.thingiverse.com/thing:19104 - as long as you got good fans and PLA and you know your overhangs are in order.
Dump truck is pretty quick.
The dogs would know about that ultrasonic whistle! Hehe…
Mustache rings are quick and painless.
http://www.thingiverse.com/thing:5123
http://www.thingiverse.com/thing:20479