The project I remember most fondly was pretty darned cool (or more likely I was too young to realize what a dork I was becoming)* and I use this technique to 'spruce up' wilted, sad greens from the Farmer's Market.
Does this happen to you? You've enjoyed a leisurely Saturday morning with family or friends, walking to market, perusing the local bounty, sipping coffees downtown only to find depressingly limp greens in your shopping bag when you (finally) get home?
Just chop the bottom with a knife, (a serrated one works well for woody stuff like bunches of oregano) and put your greens and herbs in glass jars or containers and leave them on the counter or in the fridge. Never again will you have limp greens! It's science!! (which I think is just... Magic: Explained). It's like having a little counter top garden and the duck has fun picking herbs from it to add to her noodles and cheese.
The (boo-urns) bok choy above has had the water evaporated from it's cells. The plant cells themselves get all limpy and kind of empty. Think of a garden hose that has no water in it, it is sort of like that. When you add the greens to water, the plant sucks up the moisture and the cells fill back up again and are firm and lovely. Just like your full hose. Tadaa! It's Magic!!