Yes I second that - it is too late when a white screen with a "!" crash comes, by then the right click option is gone..
Also, whilst memory leaks are an issue, they aren't always the cause of this crash. Why? Firstly, as an example, I was playing a skins game on merion. My approach shot landed about 7 foot above the hole, and when I putted, it missed, started rolling off the green, and then I got the "!" crash. So I cleared my flash and browser caches, and then restarted my browser. Got back into the game, has a chip shot, it again went past the hole in a similar spot to before. Took the putt, missed the hole again, and it gave me another "!" crash. So if it were a memory leak, it occurred after 2 shots only! (remember I cleared all my data).
Also, several programmers on the adobe forums have reported being able to reliably reproduce what they call the GCOD error (grey circle of death) - aka this "!" error. And one way is to set a vector to a negative value. Either way, this bug is costly. Hope wgt can look into it properly.