Yeah, I'll jump in and say the Scallion as well.... mine has a billion miles on it and it still going strong... still a joy to carry.
Real inexpensive but insanely practical is the KA-BAR Mini Dozier Folding Hunter. Thing disappears in your pocket, and is a breeze to maintain.
The Spyderco Dragonfly is a great piece. I myself like the VG-10 Blade and foliage green G10 handled model. Top of your price range, but totally worth it.
About half the price of that Dragonfly is the Spyderco Cat. Great steel, great handle, great company. And it has a liner lock instead of back lock... I prefer the liner lock myself.
Now I don't have one of these, but it's been in and out of my cart enough times that I'll probably pull the trigger and find one... The Boker Plus Stubby Kwaiken.
It has S35VN steel, carbon fiber and titanium handle, it's a ball bearing pivot flipper, and it's just plain (IMO) neat as hell. Maybe I'll click the buy button tonight.
This Blade HQ Exclusive Stubby Kwaiken Flipper has titanium bolsters, marble carbon fiber handle scales and a satin CPM-S35VN steel blade.
www.bladehq.com