I was inspired by sysfunboost.sh (swaps two system binaries) and made fun-boost.rb which does the same thing with two methods.
https://github.com/lmc/fun-boost.rb
A reminder that MTGOX originally stood for "Magic The Gathering Online eXchange". When a site designed for trading cards online turns into the world's biggest Bitcoin exchange you better believe there's not going to be an appropriate level of security underneath it.
As an ex-developer of a company who had servers co-located with them, I'm feeling mighty smug about using our own backup system instead of their in-house one.
As mentioned earlier, bandwidth in Australia is prohibitively expensive so the choice wasn't as simple as "use both".
Depends on your tolerance and method of usage, but I use it 2-3 times a week, using a vaporiser, and go through ~0.1 grams a session. Due to taxes where I live (Victoria, Australia) it's cheaper than alcohol.
If it's anything like SNES/Genesis/other console emulators, the only entropy source is player input. I can't imagine many arcade machines would have a true persistant clock, and even then you could just store the start time as part of the replay data to ensure you get the same output for rand(time()) each time.