@TildalWave Doesn't Chrome have its own Flash player? If so, that's what it'd suspect. Although, in my experience, Chrome eats memory in general. Some sites (Twitter, I'm looking at you) are worse than others.
It's not uncommon for me to find my various Chrome processes to be using 2GB-3GB of RAM between them, unless a tab (Twitter, I'm looking at you) has gone haywire then it can be significantly higher.
@Rory I have to admit that the only reason I haven't done anything with keybase.io is that the fact that the OkCupid guys are behind it sets off all kinds of alarms in my head. Not that any of them are reasonable, necessarily, but I haven't been able to get over the obstacle that they present yet.