There's also a great free (SIL-licensed) typeface for signage: <a href="http://pixelspread.com/allerta/" rel="nofollow">http://pixelspread.com/allerta/</a>
Since it doesn't seem to be linked anywhere <a href="https://github.com/mapillary/traffico" rel="nofollow">https://github.com/mapillary/traffico</a>