[murbard2]

I own the "Etymotic Research ER20 ETY-Plugs", about $13 on Amazon Prime. They're much more comfortable than the cheap foam ones you can buy, they actually stay in your hear, and the tube means that you can still hear high frequencies. They reduce the surrounding volume rather than attempt to mute it. This makes them great for concerts.

There are also much more expensive concert earplugs for musicians, which do an even better job at preserving the spectrum, but I'm not that picky.

[TheLoneWolfling]

I have the same ones. They are great, although I find them getting uncomfortable if wearing them for an extended period of time. Then again, I haven't found a set of earplugs for which that is not the case, so take that with a grain of salt.

[ZoFreX]

These are great for concerts (assuming your ear canals are long enough - these are far too long for mine) but not so great for a flight situation like in the article. For blocking out as much noise as possible, foam plugs are much better than these.