Not sure if it's technically a sale since it always seems to have the price marked down, but Spigen's Tough Armor case is on sale via Amazon for $20 (you save a grand total of $15). They also have a Slim Armor for $17, marked down from $30.

Of course, is this really a sale? I'm not sure since, speaking for Tough Armor only, it always seems to be marked down to the price listed.