TomTop offers the SQ11 1080p DV Mini Infrared Night Vision Concealed Camera in several colors (Black pictured) for $9.99 with free shipping. (Anderlink via eBay charges a few cents more.) That's the lowest price we could find by a buck. It features a 140-degree lens, clip, and mount.
Note: This item ships from China and may take up to six weeks to arrive.
What's the most maddening fee you pay? To check your luggage? Bounce a check? Use an ATM? Not even close.