I have embarked upon an adventure into the art and science of zymurgy after thinking about it for a few years. I am a hobbyist but the beer I produce is delicious and quite enjoyable. I find that home brewed beer is better than mass-produced beer in many respects, not the least of which is the degree of control over all the aspects of the process. Anything you see at the store you can make and it's fun too!
I have been making a variety of ales fermented at room temperature and I have a refrigerator and temperature controller for making lagers. I started making all extract recipes but now I'm brewing all grain all the time. There is better control over the composition of the wort using grain than using extract and milling it fresh is far better and yields more robust flavors than using old extract but I have made beers with grain and extract both. Since brewing is an art there are millions of ways to combine the thousands of ingredients.