(Note: this model was previously erroneously described as bacteriophage T7, which has a different life cycle entirely and looks somewhat different. Sorry! I will update the name shortly after I work out how to preserve a few permalinks. Also, I have removed metal from printing options after a customer's order failed to print; sorry again!)
By request of @TheFrogBlog on twitter, here's a model of Bacteriophage T4 which is somewhat-accurate. Source files are on Thingiverse: http://www.thingiverse.com/thing:16496
T4 is a lytic phage which has been studied for years; a bacteria-virus that can infect and destroy E.coli cells within 30 minutes.
Here's an excellent animation of T4 infecting an E.coli cell: