Amazon has got this Swingline ClassicCut Lite 12" Guillotine Paper Trimmer for $20.49 with free Prime or SuperSaver (minimum order $25) shipping. This paper cutter got 4-1/2 stars out of 5 over 7 customer reviews.
Just to give you an idea of what a great buy this is, Office Depot has got it for $37.99 (85% more).
The trimmer is 18.5" x 15" x 3.5" and will slice up to 10 sheets of 20 lb. bond paper simultaneously. It comes with a limited 10-year manufacturer's warranty. Hurry and get it at this price before Amazon pulls one of their infamous price swaps.