A way to store lettuce longer?

I have been wondering if there was a way to store lettuce and leafy greens longer than the one week expiration date.

Most online help sites say to wash, dry, and wrap lettuce in a cloth and place it in the bottom fridge tray. I do not like this idea because of lint from the cloth on the lettuce. If you do this, be sure to rinse after unwrapping from the cloth.

I am trying a new trick, but I do not have enough data to claim if this method works.

What I do is rinse the lettuce, place it in a separate tight container, a metal container in my case, and then fill the container with water. Then seal and place in the coldest spot on the fridge. This seems to preserve the lettuce longer.

Has anyone tried this, and discovered that it works or does not?

UPDATE: (04 OCT 2013)

Okay. I tried it all the way. Here is what happened: It does appear to last a little longer like several more days. The only problem I noticed is that some of the leaves may get soggy. If you squeeze the water out, you can treat it like spinach. I don’t seem to mind too much. 🙂