[favour either 3.3V or 5V.]

I'm using coin battery of 3V.
however many of the components which i'd like to use favour  either 3.3V or 5V.

can anybody recommend me how step up the voltage by:

1. other batteries recommendations(the recommended batteries like CR 1632 are 3V which I currently use )
    perhaps with different voltages

2.some circuit or method to step up the voltage(cheaply and small)

3.Is GPIO voltages i3V no matter what power source you use?
   does tiny duino step down source voltage(like the 5V usb voltage) to 3v?

thnakx

joseph.

ive been using these with great results. it's super small as well.
http://www.pololu.com/product/798

ive been using these with great results. it's super small as well.
http://www.pololu.com/product/798

Thankx alot!!