If you like the idea of currency trading www.FXsol.com offer a free 60 day simulated trial and you can keep re-applying every 30 days thereafter (it takes mere seconds). Great charting software, accurate sim using real-time data, very realistic and true.
If you do look to start testing the water with currencies make sure you keep a trading log, a simple spreasheet will suffice, and analyse your trades to see what you're doing right and/or wrong.
Sim might be fun to play around with but I wouldn't bother going live with it- looking at the website its just an FX bucket shop who'll take the other side of your order - that, in itself, throws up a whole host of conflicts of interest.