1) A bit on how planaria (https://en.wikipedia.org/wiki/Planarian) regenerate. Planaria are tiny little flatworms tens of thousands to hundreds of thousands of cells in size. They're some of the most common creatures on the planet, and if you cut an average planarian in half, it regenerates into two planarians. If you cut it in fourths, it regenerates into four. In fact, you can cut a planarian into any number of pieces and they will all regenerate, provided each piece contains a neoblast. What's a neoblast? A neoblast is sort of a super stem cell for planarians. They have active telomerase and don't, as far as I know, age, and they can regenerate any cell type. They're found diffused throughout the body of a planarian and make up about a quarter of its cell count.
Here's a little (published) anecdote to give you an idea of how powerful neoblasts are. Some scientists (named Wagner et al) exposed a sexual strain of planaria to lethal doses of radiation (some planaria strains reproduce sexually, some asexually, I believe by splitting in half). Some of these were implanted with a single neoblast from a related asexual strain of planaria. Not all of the implantees survived, but the ones that did regenerated their lost body parts, grew up normally, and started reproducing asexually. As the authors of the review where I ran across this put it, "[i]magine if a very old and sick person could inject a single stem cell, frozen away since youth, under his/her skin and rejuvenate their body -- youthful and disease-free!" In some sense, though, this is even weirder -- it's like an old and sick dying person injected a single stem cell from someone else and transformed into that person -- youthful and disease free!
2) How to install a window AC unit. To whit, http://www.lowes.com/projects/build-and-remodel/install-a-window-air-conditioner/project. Thanks Lowe's!
(Sadly, I also learned that window AC units are not allowed where I live. Oh well.)
3) Good color pairs for the color blind -- check out about 4/5ths of the way through this article for a set of 8 colors that are pretty well distinguishable even under the three most common forms of color blindness: http://jfly.iam.u-tokyo.ac.jp/color/
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