If the mouse doesn't get hot enough in hot water alone, I like to toss it under the heat lamp for a few minutes inside the Ziploc baggy. You have to keep a VERY close eye on it though, as overheating the mouse is a recipe for the guts exploding. I just like to bump it up a couple extra degrees because it seems to help my little guy take it faster. Otherwise the mousey dance is a long, drawn-out process.