Selecting a microcontroller

[Browzilla]

I'm planning a project and need to select a microcontroller. This being my first experience with microcontrollers outside of FIRST, I'm relatively in the dark as to what exactly I need.

My project needs to control 6 devices drawing 20mA each. Due to my plans, each'll have to be on a different I/O pin.

Can someone explain or help me find an appropriate microcontroller?

Features I'd like:
Cheap. I'm hoping to make a few of these projects up for teammates.

Low cost-of-entry. I don't want to have to spend tons of money on software or cables and such.

Preferably programmed in C, C++, or BASIC. I could learn something else if I had to, but this would be easiest for me.

Preferably USB interface, not serial.

I use a Mac, so if whatever software I need for this is available for Mac, that'd be ideal. That said, I could pull out the old Windows box if I needed. OS X would be nice, but low priority.