This Low-DropOut (LDO) linear voltage regulator can provide up to 500mA of current, operating from an input voltage of between +2.7V and +11.5V.

With a quiescent current as little as 15µA, and up to 1.8W power dissipation in a small SO-8 footprint (also available in PDIP-8 for large-fingered hobbyists ;-)), it is ideally suited for use in small, low-power embedded designs.

Here is a typical operating circuit: