Richard Bandler - NLP co-founder - places great emphasis on people learning to generate intense, exhilarating body feelings at will.
In therapeutic, remedial terms, you can "anchor" these states to parts of your life that ain't so great yet. This will dilute what limiting states you may have felt in those situations and give you a choice of feeling and acting in another way.
Much more profound however, (and here I shift from the second person "you" to the first person "I" - this is a personal experience Matthew!) is learning to feel good more and more. To learn to enjoy what I already enjoy more and more and with more humour, delight and fire.
NLP doesn't "do this". You do it, perhaps with someone's help, perhaps without. But the attitude you have, or that person, has is paramount to effecting a change.
It might seem I'm focussing on something overly simple here. After all, isn't NLP about subtle linguistic tricks, moving and shifting mental images, covertly eliciting peoples values and "meta-programs" and then sneakily touching their knee to "anchor" it? Well, all of those are tools that are part of the NLP model but...
...without a powerful intention, a drive, a purpose, NLP becomes mental masturbation or worse. All of the little bits and pieces of NLP only come together with that direction, that humour, that curiosity, and that strong belief in people's ability to learn, not intellectually, but learning anything and everything at a basic behavioural level.
The methodology, the NLP model's way of approaching consciousness and mental and behavioural patterns, comes second. Finally, as Anthony highlighted, comes the trail of techniques. And if you can't profoundly affect another or yourself and lead them into a state of laughter, or yearning, or delight, or hope, using your voice tone and facial expressions or gestures, then any "swish pattern" or "anchoring" you attempt will be consistently and systematically ignored by your brain. The neural stimulus you create in that person or yourself will have the same level of impact as the slightly irritating buzz a fly makes in the corner of the room.
Imagine a computer engineer with fantastic knowledge and a box of precision made tools at hand, but an inability to even turn a screwdriver. He kind of scratches the screw a little and then sighs.
So to answer the original question, using NLP and having trained in it has been a major factor in keeping my sense of humour about me (and there's a nice ambiguity in that phrase) and quite literally learning to expand my range of feeling good, for a good few years now. The refinements and subtleties of it, and how to be a little more covert with people when necessary, are what I'm still learning.