RAIDer is a must have application for any IT professional or the do it yourself home-brew who deals with the configuration and maintenance of RAID storage.

In manual mode, RAIDer lets you select a RAID type (0, 1, 5, 1+0, and 0+1 -- more coming), a number of disks, and the capacity of each disk. RAIDer will then show you the effective size of your array, and give you some information about the RAID type you've selected.

In optimizer mode, RAIDer lets you enter your desired array capacity and attributes (maximize spindle count, fault tolerance) and will select an appropriate RAID configuration for you. You can then move to manual mode if you want or need to adjust the parameters the optimizer chose for you.

Edit the available disk sizes to customize to your setup and environment.

It's quick and easy, and I have several additional features planned and in the works.