Well, desperate, not so clever. In my determination to cover my seedlings at night I carved the botton off of a Tidy Cat Plastic Container and a big old Hawaiian Punch plastic bottle. I'm also using a Folgers empty plastic container on a tomato.
I'm better prepared some years and have saved back gallon milk jugs which are GREAT with the bottoms sliced off. You can easily vent the container by taking off the cap.
I wish I drank more pop so I had some liter bottles to use but noooo, June 8th and I'm scrabbling for things to protect my babies from the cold.
On the plus side I seem to have plenty of empty tp rolls to use as cutworm collars for my seedlings...