What's your least favorite weed?

This year, a form of bindweed is topping my list of unwelcome garden greenery. It's a fairly recent invader that made the jump from not far away, and it's creeping its way around my alley garden, even creeping up other weeds. How embarrassing is it when your weeds are weedy?

A few weeks of not being able to get into the garden have left me with a laundry list of usual suspects, including prostrate spurge, purslane, clover, volunteer elms and maples and whatever that thing is that looks like some variety of pigweed. All those are fairly easy to pull, especially after all the recent rains, but that bindweed is annoying to unravel once it's snuck its way around lilies.

What's on your list of least favorite weeds? And do you know what it's called? (I spent some time online trying to find the actual name (not profane) of one of the weeds I was battling.)