SkyFonts - Sync Google Fonts to your Windows PC or Mac
Looks good, although it does require a free Fonts.com account in order to sync the fonts (in addition to the .NET Framework v4.0).
Website / Download (Windows: 32-bit / 64-bit, Mac: 64-bit)
We are proud to have teamed up with Google to offer desktop versions of their popular Google Fonts free of charge. Offered for use in print, these fonts are delivered using SkyFont’s patent-pending font delivery technology and can be used anywhere.
Each time a font is updated — such as when new characters are added — SkyFonts will automatically update the font on your device. Syncing Google Fonts with SkyFonts will also improve your web browsing experience, by cutting the time spent downloading fonts.