Human-Computer Interface - There have been numerous studies and research papers about reading thoughts with the help of computer. It's still a far cry from practical applications, but scientists have managed to read and recognize emotions triggered when viewing certain images. There have also been few attempts to allow human mind to work as a processing unit for external limbs.
Suggestion - It's more of an illusion than actually reading one's thoughts. Mentalists and magicians use this method to first imprint certain thoughts into your mind (through repetition, subliminal messaging and associations) and then act as if they were reading your mind.
Behavior Patterns - It's a study of common human behavior. Not reading thoughts, but more about statistically viewing the most likely behavior in a given situation. For example, did you know beautiful women are much more likely to receive help carrying bags than ugly women? Marketers and salesmen often use these techniques to maximize profit (which is why most products are advertised as new and cool, rather than 'the same old stuff').
Telepathy - There's no scientific proof that some people would poses these esoteric skills of reading one's mind, but there are studies explaining telepathic experiences via empathy and micro expressions (tiny facial movements people recognize subconsciously).
Sometimes you want to read human's thoughts. Has anyone heard where it is possible to learn it? I am sorry if this question is not related to the topic.
You cannot learn to read people's thoughts as something final like learning to drive a car. But you can get good in reading other people as what are their feelings, intentions, opinions, how they think...mostly by guessing while connecting some signs; as for some kind of formula for reading people, I don't have one. You may try by guess and see. Make your impressions of people's thoughts/feelings in some trivial things and then check if it's true. If you were right most times, you have 'good reading skills' if not, well either you're really not for it or maybe just not natural for it and you can work on changing your perspective based on which you made your judgments.