SkyFonts is a small tool which can install Google Fonts (Google's collection of more than 1,100 professional fonts) on a PC or Mac for offline use, automatically update them as required, even synchronise these fonts with all your devices.
For this to work you must first create a fonts.com account, if you don't have one already (click Services, sign in, and follow the instructions).
Next, click Services > Google Fonts "Manage" > Google / Fonts.com, and a browser window will open at the fonts.com site. Click Browse Google Fonts, and you'll be able to scroll through and view the various Google Fonts. If you see something you'd like to use, click SkyFonts > Add > Close, and it'll automatically be downloaded, installed and become ready for use on your computer.
By default SkyFonts sets itself up to run when your system starts. This is fine if you'll be choosing new fonts all the time, or will make particular use of the program's sync feature, say, but otherwise it's not such a good idea. Especially as the program uses a surprising amount of RAM (44MB on our test PC). But you can at least turn this off via a configuration option (click Advanced, clear "Start SkyFonts on machine startup").
Maybe we're missing something, but we couldn't see an option to remove a font from your PC, either.
Otherwise, though, SkyFonts works well enough, and it's an easy way to install some great fonts for offline use.