Internet-wide hiscore with some hack-protection

Continuing on the local-hiscore and inet-hiscore-basic ideas, a more hack-proof internet-wide hiscore would be even more fun. But this is really only needed if the game gets popular. Some ideas for hacking-countermeasures: base64/bloated php-http-requests, crc32-sums of game source code on boot (to check that user hasn't modified the source), https communication instead of http communication..