If your are looking for a genuine free web hosting plan for your PHP / MYSQL site with reasonable web space and features, then you don't have to search anymore. Out of many free web hosting sites available online, biz.nf seems to be the best of the lot as far as providing free web hosting with basic necessary configuration and no advertisement is concerned.
They do have Personal and Business plans where they charge monthly fees for extra facilities but the configuration offered under free plan is more than enough for a website which is small and doesen't require lot of bandwidth and space.