I am currently trading with $100 in an account using 1:20 leverage. I have up days and down days like any trader, I can feel the sting of losing money (especially when I lose $7 in one trade - that really stings). However, there are a few noticeable differences that I see by trading that small:
1) You can only trade one position at a time. I entered a trade this morning for 1 micro on GBP/USD and my margin required was $67, leaving me without enough margin to open a second position.
2) Unless your broker offers flexible position sizes or you have really tight stops (like 10 pips), you will not be able to implement a 1% or 2% risk rule. You will be running closer to 5% - 10% account balance risk per trade.
3) If you make $3.00 on a trade, you did good - the raw dollar value might seem insignificant, but it is a good percentage of your account. Likewise, losing $3.00 may not seem like much, but treat it like a big deal.
4) If you blow up your account, it's easier to get back in the game as $100 is much easier to come by than $1,000.
I opened my account about 6 months ago, so I am still very much learning and getting comfortable trading. Sometimes the one position limit frustrates me as I spot multiple good opportunities, but it also forces me to be selective with my trades. The things that I really like about my tiny account is that if I blow it up I don't take that big a loss, and I can afford to test new strategies in that account.