This may rub some of the more meticulous types the wrong way, but... I leave a couple of batteries fully charged, sometimes for weeks on end. Haven't noticed any downsides. I just don't want to have to charge the batteries when I decide on a whim that I want to run my RCs around the yard.
Wisdom is that the chemistry is more stable when they are half charged, my cells may get unbalanced more as a result, and they may not have as long of a service life. But these batteries were $17 and $25 (Turnigy brand) and they've lasted 30+ charges over about a year...
Don't sue me if your house burns down. I do keep mine in a LiPo bag just in case.