A euphemism for sex, used a bit in a popular thread on the MegaTokyo messageboards by BozoCat, in the thread MT:tC of ph34r and b33r. Typically, BozoCat's character in the thread(which is a forum RPG), Nicholas, has used it a bit.
Sayt: "So, have you uh... Blender... With her yet?"
MS: "wait, WHAT?"
Sayt: "never mind."