It is a truth universally acknowledged, that a single man in possession of a lot of crap must be in want of a shelf to put it on.
My kitchen and dining room was kind of a mess. The island in the kitchen has a small shelf (which I call a microbar) suitable for eating a quick meal off of, but it was entirely covered in cookbooks and recipes and my TI-83 (which after years of faithfully solving calculus problems now exists solely to help me scale recipes). I decided that my engineering degree plus my Y chromosome would help me create a shelf.
I bought some wood and some wood screws at Lowes and went to work.

I bought two sets of screws: one too short, one too long. I decided to use the short screws and then I would use the big bit to bore an offset hole to sink the head in. It shouldn't affect structural integrity any but may actually make it look slightly nicer, not that aesthetics were anywhere near the top of the goal list for this project.
Also note that I don't have a workbench of any sort in the garage, so this project was done entirely in the dining room. This is one of the reasons why I'm enjoying being single; I didn't have to hear "when are you going to finish that stupid shelf so we can use the dining room again".

Despite my utter lack of carpentry prowess, I managed to finish constructing the failshelf today. We're not going to talk about when I
started constructing it.

A common comment I got when describing this project to friends was "you know, for a lot less effort and money you could have gone to Target and bought a better-looking shelf". I'm not going to dispute that, but I don't think I would have learned nearly as much or felt nearly as satisfied. When I was putting the first shelf on, it took me probably ten minutes per screw or more (!). By the last shelf, I could knock all four screws on a side out in maybe five minutes or less. I wouldn't have learned as much assembling one of those "insert tab A into slot B" shelves you buy out of pressboard and laminate.
See all pictures
here