FXCM and other brokers now also offer micro accounts where one lot is only 1000 contracts, not 10000 as in a normal mini account.

Micro lot accounts have two advantages. You can trade with less money - margin is only about $5, so you need very little money in your account, even $200 can suffice for a start. Also, Zorro can better adjust the the trade volume due to the finer granularity. This gives slightly better profit. It is therefore recommended to open a micro lot account when your broker offers it.

BUT: With FXCM even micro lot accounts have standard lot sizes for CFDs, indexes and commodities! So when trading with SPX500, XAU/USD and so on you still need a margin in the $50 range.