Priceline.com launched a cool new iPhone application today that not only functions well but is also really fun. Finally, a great app from an established company that also has some whimsy. Priceline is obviously serious about mobile bookings but isn’t taking themselves too seriously with this app - we like that.

Most importantly, this isn’t just a re-skin of the regular Priceline website crammed down to fit on a small screen - The Negotiator app is actually a different experience tailored for the iPhone and a fun one at that - the music between the screens adds to the fun.

Most fun is the “shake down” feature which leverages the iPhone’s location functionality to display winning bids nearby. Shake your iPhone and see what your options are - perfect for last minute bookings and much more useful than a randomized restaurant listing!

It is also easy to toggle between “Name Your Own Price” hotels and regular, published hotels through a tabs at the bottom of the screen labeled “Negotiate” or “Browse.” When “negotiating,” the app allows users to perform Priceline bidding functions with some nice touches for choosing your bid amount like a recommended price to bid, and a slider to increase or decrease the bid with great tag lines like “See if you can bag this deal, too!”

And because you can book up until 11PM for same day arrival, we bet more than a few travellers who find themselves stuck in a city for whatever reason (you can think of a few, I’m sure) will love this app. Priceline has long allowed for same-day bookings but firing up your laptop for a last minute room isn’t exactly a lot of fun - Priceline has created an elegant and fun solution.