Best water heater blanket?
 

Looking to get one for my mom before I head back to school in a few days. Is there one brand or type that's better than any other, or should I just head down to Home Depot and pick up whatever looks pretty?

AFAIK they are all just fiberglass insulation. Take note of what R-value you are buying is all.

I think any old thermal blanket designed to fit a tank works well. Be extra careful if her tank is gas..
I have a gas water heater but haven't put a blanket on it. In the summer it is so hot that our cold water scolds my hands.

It is a gas heater. It doesn't get horribly hot though.

Have you already turned down the water heater temperature?

Yeah, to 125 or so

i tried buying one last year, but there wasn't one large enough to fit my hot water heater :( I'll look again this year.

Just about any wrap will work fine. Bear in mind most of the heat comes out on top. Be careful not to block airways.

Also it is far more important to drain sediment out of a gas fired water heater than an electric, crap falls to the bottom and insulates the water from the fire. How often is up to you.