Cutting Fiskars 12" Rotary Trimmer --- I used to use the Provo Craft Paper Trimmer, and it was okay; I went through a lot of blades since it wasn't a rotary cutter and almost always seemed to have some sort of 'fuzz' along my cut before I splurged and bought this. I used a 40% off coupon at Michaels to help cut the cost a little!
Good Scissors (Full Size)-- I use the Corporate Express Brand, and they are from one of the office supply stores, and scissors you do decide to designate for paper only, I recommend you write that on them, and make it clear throughout the household; it's amazing how quickly a pair of $20 scissors can become useless (not like I'd know....)
Better Scissors (Small, for detail)-- Cutterbees; I swear by these little scissors. They can cut everything (big or small) and always stay sharp. I clean them every so often (like few months) and they have never failed me. Be careful though, these seem to attract my three year old like a bee to honey (must be the pink color... and sharp blades).
X-acto Knife-- Mine is pink, but even if it wasn't; these are very inexpensive and so helpful! I've used it for peeling stuff off my Cricut Mat, or quickly trimming spots that didn't cut. Overall, very useful for the price.