I am usually in need of powering my microcontroller projects with 5V. Typically this is not a problem, as I use any power supply (converted PC power supply, wall adapter, USB, etc.).
However, when I need my projects to be portable and lightweight, I am not quite sure what the cheapest/easiest way to accomplish this would be. The additional requirement is that I would like to use 3.7V LiPo batteries. This is simply because they are much smaller than any other solution, and can pack a lot of power. Also because I have many lying around.
If I was using something higher than 5V, then I would just use the L7805 to drop it down, or some other solution. So how would I step up the voltage from a 3.7V battery to 5V in the cheapest and smallest way possible? Is there a widely used IC which accomplishes this task?