A regular lottery within a regulated environment returns about 50% of its players' investment on average. Playing that is idiotic. The Bitcoin lottery returns more than 100% of my investment on average on the current conditions (basically only 240 watts of electricity). The chance is there, that I could never find a block (which luckily didn't happen), but if I find a block, its return is high enough to justify buying the ticket (on average more than 100%). So playing the Bitcoin lottery has both good returns, moderate risk, and it is fun. Beats Las Vegas in 2/3 aspects. Pooled mining would also return more than 100% right now, but with zero fun and much time wasted for a wimpy return (or considerable risk if you scale).

PS Does anyone know, how I can find out which block my miner has exactly found? The Bitcoin client only shows time, amount, and pending confirmations.