The ATTiny85 is a lovely little workhorse of an IC. Now supported by the Arduino IDE you can stick a bootloader on it and program it as you would an Arduino (with an Arduino no less!).
We use them in our TinyCylon and you can also use them to control WS2811 based strips!
Series AVR® ATtiny Core Processor AVR
Core Size 8-Bit
Peripherals Brown-out Detect/Reset, POR, PWM, WDT
Number of I /O 6
Program Memory Size 8KB (4K x 16)
Program Memory Type FLASH EEPROM
Size 512 x 8
RAM Size 512 x 8
Voltage - Supply (Vcc/Vdd) 1.8 V ~ 5.5 V
Data Converters A/D 4x10b
Oscillator Type Internal Operating Temperature -40°C ~ 85°C