I took a large coffee cup I purchased for $1.69US, a small 4 oz desert crock that can be picked up at Wal-Mart (2 for aprox. $4.50US) and took it to a hardware store to fit it for a rubber O-ring (.78US). The crock fits perfectly inside the large coffee cup.
I fill both up with hot water and jump in the shower, get out and empty the small crock, dry it out and put it back into the coffee cup. Lather up and enjoy nice warm lather for at least 3 latherings. (I use it with Colleen's lavender shaving cream)
If interested in making your own scuttle, Idaho Mike posted a great thread some time back.
http://straightrazorpalace.com/showthread.php?t=8014
Check it out. He's the one I got my idea from.