Yes, if you use Font Awesome with Bootstrap! The icons are slightly different, but there are more of them, they look great at any size, and you can change the colors of them.
Basically the icons are fonts and you can change the color of them just with the CSS color property. Integration instructions are at the bottom of the page in the provided link.
Edit: Bootstrap 3.0.0 icons are now fonts!
As some other people have also mentioned with the release of Bootstrap 3.0.0, the default icon glyphs are now fonts like Font Awesome, and the color can be changed simply by changing the color CSS property. Changing the size can be done via font-size property.