I've used 000webhost for a number of years for either building test websites or for very low budget sites.
The downside with them is that they are quite agressive with unused sites, e.g. if not enough people visit (or you logging in) then you get popup ads, if you get very few hits then they see the website as no longer being used and will delete it to save their server space (they claim to give you advanced warning but I haven't always found this to be true!).
So there is free hosting out there but I would now be seriously tempted by the £15/year mentioned above (TSOHost is regularly recommended on these forums). Free hosting is invariably more hassle for you so I'd ask yourself whether it'll cost you £15 worth of your time and effort.