I wasn't at Mid-Winter, but I ran a couple one-shots in late December, and my winner for clever use of a Variation probably goes to my second playtest group:

The Mutant with Translocation could only teleport to places she could either see (difficult, given the security of the area they wanted to access) or where she had left significant traces of her DNA (some hair, blood, etc.). So, she got her hands on some gum, chewed it up good to make sure it had enough of her DNA in it, and then stuck it to the undersides of food carts, the shoes of guards, and other objects that were bound...