Thermal Masks - a drugstore alternative

Within the makeup community everyone has been raving about MAC's Volcanic Ash Thermal Mask from the recently launched Style Black collection.  Here is the description of the mask from http://www.maccosmetics.com/

"Formulated with Volcanic Ash and natural oils, this ash-black facial mask simultaneously deep-cleanses and treats the skin. When water is added, the mask heats up and the oils instantly lubricate the skin, leaving it feeling soft and clean. Helps keep skin moist, clean, soft, and evenly-textured. Limited edition."

This mask went flying off the shelves within days of the release and is sold out online.  It was $19.50 for a 3.4 FL tube.

I however, have been using a drugstore version of a thermal mask for a year now and I am glad I didn't rush out to the MAC counter to grab this mask.  I've been using the Biore Purify Self Heating Mask. 

The box contains 8 packets for around $7.99 and can be found in any drugstore that sells Biore products.  It isn't the traditional mask that you apply and let it dry on your face for 10 min then rinse off.  First you moisten the face, apply mask, massage for about 1 minute then rinse off.  The mask instantly heats up on contact with water and it feels amazing.  It removes pore-clogging dirt & leaves my skin smooth and radiant. 
So if you skipped out on the Style Black Collection or you didn't get a chance to pick a Volcanic Ash Thermal Mask before it was sold out, you always have this alternative. :)

Have you tried any other thermal masks out there?