If you’re curious to try out Firefox OS but don’t fancy trying to shoehorn it into an existing device then the next best option might be to get a new device with this OS already on it. You may think that this could break the bank but you can actually get a device fairly cheaply.
If you have a look at this page on Mozilla then there are a few links to pickup a ZTE Open from eBay for under UA$100. Whilst it isn’t an Android phone or iPhone it is potentially affordable for most people. Plus, if you’re just after a cheap phone that will make calls, text messages and web browsing then this could fill the gap rather nicely.
I’m not planning to pick up a handset for myself but for under $100 it is a price point that could easily pique the curiosity of techies. The ZTE Open handset itself may not be fantastic but enough to give you a feel for it.