If you're looking for an iPad mini case that allows you to throw around the tablet a bit without it getting beaten up too much, the OtterBox Defender is a great option for that.
The case is made out of thick polycarbonate, which is nearly unbreakable and protects every part of the iPad except for the screen. The screen is protected with a built-in sheet of tough plastic that protects the display from scratches and other rough doings.
Even the ports are covered with rubber flaps that can keep dust and dirt out with ease, making it a great case that lets you take your iPad to the beach without any worry about getting sand in it.
The OtterBox Defender is priced reasonably well for what you get, costing just shy of $40.