I decided to head over to the studio without my lights, modifiers, variety of lenses, PocketWizards and all the rest of the equipment I normally take with me. I did everything with my 7D and a 50mm lens. I started doing this every now and then awhile back. It began as an exercise to help remind myself that if worse came to worse (broken or lost gear, lack of power, etc.), I could always walk away with good photos. It's a confidence builder as well as a great way to just let go and shoot. Not a bunch of lighting setups and settings to concern myself with; just me, the subject, and the environment to make good photos. I'm doing this much more frequently these days.
Sure, I love the gear. Just putting the lights up and figuring out what I want to do next with them is always exciting. But I also love to just shoot loose. The flow of a shoot becomes much more casual and spontaneous. The results, while not as slick as a well-crafted studio setup can produce, will often be more organic and have more "feel" to them, if you know what I mean.
By the way, shooting with a stripped-down kit is one of the things I talk about in my book, 15 Photo Projects That Will Boost Your Creativity. Of course, there I talk about sticking to this single-lens (and no zoom allowed) shooting constraint for a week straight, and that's a challenge I'm not sure everyone's up for. But there's nothing hard about leaving most of your gear behind once in awhile. Give it a try.