Now that seemingly every other movie that opens wide in the multiplexes is a $150 million+ blockbuster-in-waiting (or, in many instances, a small fortune down the toilet for the studio), just about any movies smaller than this are liable to be classed as 'microbudget.' This label tends to be applied to the output of the likes of Blumhouse Films, the company behind a significant portion of today's mainstream horror releases (Insidious, Paranormal Activity, The Purge etc.), who famously adhere to a rule of never spending more than $5 million on a movie.
This might seem small change in a world of Marvel superheroes and near-photorealistic CGI creations, but, for the vast majority of us, $5 million is still an inconceivable amount of money. And the truth of it is, movies can, and routinely are, made for considerably less. The influx of digital technology which has all-but taken over the high end of film production has also seen a far higher standard of affordable camera equipment made accessible to a broader spectrum of people, creating new realms of opportunity in independent filmmaking.
One region of the film world where lack of funds has rarely been a concern is horror. The words 'cheap and nasty' are often associated with the genre for good reason, as they're frequently applicable to the kinds of macabre movies made at a low-to-no budget level. And they prove that money doesn't count for everything; as long as filmmakers bring enough creativity, energy and spirit to their work, they can make horror movies better than anything coming out of Hollywood of late (alas. this routinely means filmmakers working unpaid, with little chance of making much money afterwards - but that's another story).