Forex Trading Platform.

Well, the only thing that might be of remote interest to you is GNU Cash (http://www.gnucash.org/). However, I know that this is probably not the solution you are looking for but maybe it can be "tweaked" a bit in order to make it work for your purposes.

There may be local (non-web) clients to trade Bitcoin which are free as in freedom. If your FOREX trading platform has a public API, then you can develop or hire a developer to write a free software client; you may use one such Bitcoin trading client as the starting point.

Foreign Exchange Trading with Free Software

FSF.org maintains a list of free software, which constantly needs update help. :)
http://directory.fsf.org/wiki/Category/Business/stock-market

Trading is about creating or following effective systems. If you have a good conceptual grasp of Perl, financial analysis, statistical matrix systems, and general trading principles, I recommend tools from the 'R Project for Statistical Computing', especially the finance side.
'Rmetrics: Financial Market Analysis with R'
http://www.rmetrics.org/

If you dislike using a command line, try 'R GUI Projects'
http://www.sciviews.org/_rgui/

'Genuis Trader' is an old libre program one can use to build or manage trading systems.
http://www.geniustrader.org/
Another libre program called 'Chart' can hook into 'Genius Trader', pulling data from many online sources.
http://user42.tuxfamily.org/chart/index.html

'Show Me The Money' may be of interest, although it, like Genius Trader, pulls data from Yahoo Finance. It would be better to retrieve data directly from exchanges, but that would require a code rewrite.
http://dirk.eddelbuettel.com/code/smtm.html

To my knowledge, there is not currently a fully libre system available to investors, but maybe several of us could join together to create one?

Useful investment websites for traders.
http://dailyreckoning.com/
http://www.nestmann.com/
http://www.sovereignman.com/
http://www.traderdaily.com/
http://traders.com/
http://www.world-stock-exchanges.net/

Watch this interview with Tony about his book 'Money: Master the Game' from last November. Please, at the very least, watch from 1:24:00 to the end. We hope that Tony and many others will become advisors as we create Libre101 education courses.
https://www.youtube.com/watch?v=LPCfhshWg54

For visiting readers, Wikipedia explains the history of forex.
https://en.wikipedia.org/wiki/Foreign_exchange_market

Wishing you the best of luck trading.
Live Free & Do Good Things!

Just remember that the house always wins in the end, just like in Vegas. It's not a level playing field.