This fuse calculator for AVR microcontroller supports 144 devices.
You can set the fuse bits manually (supported are low, high and extended fuse) or use predefined settings.
Those features make it very easy to set the fuses. For example, instead of setting the clock bits manually you can just select "Int. RC Osc. 8MHz".
After setting all the fuses, you can see the commandline for AVRDUDE to flash the fuses.
The most used controllers can be set as favorite (click the star in the top right corner). Favorites will always be at the top of the device list and marked blue.
Please report all errors you find (especially default fuse settings). It is really easy (Menu -> Report error) and helps everyone.