I just went through a process of @font-facing a website for one of my projects and I have several things to add:

1. Don't bother with direct font editing. Instead use a vector editor like Inkscape [1] to save your icons as SVG and then convert them to a complete font-face kit with IcoMoon [2].

2. IcoMoon will also let you cherry pick icons from a large number of both free and commercial icon packs. This is a great starting point, especially at the sketching phase.

3. A better way to browse icon packs though is with Fontello [3]. Same packs, snappier interface.

4. FontSquirrel font-kit generator is really good, because it does a great job (re-)hinting TTFs so that they come out looking better in smaller sizes (10-14px)

  -- but --

There are fonts that FontSquirrel generator doesn't process correctly. It would happily spit out an @font-face kit, which will look normal most of the time. However on selected Windows boxes the font will render without anti-aliasing, naturally making it look like butt. It doesn't appear to depend on the Windows version (saw it happen on XP and W7) nor the browser (saw it on IE and Firefox). Also, same machines will render all other font-face kits just fine. I spent a couple of days chasing the cause, but then gave up because I found a simple workaround.

The workaround is to serve OTFs. Instead of specifying .eot, .woff, .ttd, .svg in your CSS, list .eot, .otf, .woff, .ttf, .svg. OpenType files are generally heavier, but they also compress better, so it's a wash in terms of a I/O hit if served over gzip'd HTTP.

In other words -

  +----------------------------+
  | Make sure to test the hell |
  | out of your font-face kits |
  +----------------------------+

To that effect, Adobe Browser Lab [4] includes a version of Firefox that exhibits above behavior. However, the Lab also includes a version of Chrome that pixelates all fonts, because it appears to run on a machine with anti-aliasing disabled at the OS level (yes, it doesn't make any sense, must be some sort of an inside Adobe joke).

So, the testing strategy is to get a proven font-face kit, like Open Sans, and check that both your font and this litmus font render well. If both look aliased, then it's the OS issue. If only yours does, then it's a problem with the font-face kit.

[1] http://inkscape.org

[2] http://icomoon.io

[3] http://fontello.com

[4] https://browserlab.adobe.com