There's not much to nerd culture, really. Pocket protectors, high-water cuffs, high SAT scores, the attitude.
I do a lot of writing, and if you see me in public, chances are that I'll be wearing my Nerd Pack (pocket protector), complete with five writing instruments. I really do feel naked without it.
I believe that writing instruments have a strong effect on the style and legibility of handwriting, so over the years I've always had a serious tool fetish for pens and pencils. I've refined my choices over decades, and here are my current favorites.
Faber-Castell technical pen with #2 (0.5mm) drawing cone. Completely unavailable in the USA; I was fortunate to get a supply from a friend in Austria. The American version, the Koh-I-Noor Rapidograph, is greatly inferior; the ink reservoir is way too small and it tends to clog a lot more.
The only really critical ingredient is the ink: Pelikan FountIndia. A friend of mine who uses this ink to make biological specimen labels says it is indelible even after several decades of immersion in alcohol. This system writes on any kind of paper, even through fingerprint oils, and makes for a very clean line. This ink is not easy to find. I had to order mine specially through an art supply store.
Faber-Castell TK-Fine Vario L 0.5mm automatic pencil. Although this is a bit pricey at around $10, I love it---it's a fine instrument. Good feel, holds a ton of lead, and although the eraser is not that large, it's always exposed and comes in a two-inch refill that can be cranked out. Has a hard/soft control that enables or disables a spring to prevent lead breakage under pressure. Thanks to my colleague Alan Contreras for recommending this. Available from Levenger.com.
I used to favor a terrific, cost-effective American product, the Scripto P200 automatic pencil. These were cheap (under $2 single quantity, cheaper by the dozen) and also had a huge eraser with nothing covering it, and a spring to prevent lead breakage. They also had a 0.5mm cleaning wire inside which was very handy for clearing jams. Unfortunately, Scripto seems to have gone away.
I'm also hooked on Staedtler-Mars Plastic erasers (526 50), and the Pentel Clic Eraser ZE-21. They are the only thing I've used that erases really thoroughly on National engineering pads. However, generally my pencil's built-in eraser can handle minor corrections, so I tend to keep one of each wherever I do a lot of design work, rather than carrying them around all the time---who wants to carry all that junk around?
I need a backup pen because (a) fountain pens are cantankerous, (b) they won't work on multi-part forms, and (c) the ink can bleed through some kinds of paper. So I carry a Paper Mate Gel Roller, XF (0.5mm), in blue (which also gives me another color choice over the basic black ink). It's not the perfect instrument either, sometimes skipping a little in the presence of skin oils, but it's much better than most of the gel rollers I've used. My second choice would be Sakura's Gelly Roll XPGB (purple). For some reason, only the purple ones (and only some of them) resist skipping on skin oils. Advantages of the Paper-Mate include: blue ink (more professional); a better pocket clip; and a finer line.
The main function of this pen is marking corrections, especially on program listings. I want red because it's hard to miss, and also traditional for marking homework. Currently a Sarasa gel roller, red, 0.7mm. This was a random choice off the rack that seemed to work pretty well. Looks like the very similar Pilot G-2 gel pen is a good choice, and unlike the Sarasa it is also available in 0.5mm.
In black. Writes on anything---glass, film, CDs, bathroom walls, food wrap, plastic bags. Good for making posters or leaving notes where a smaller line might get ignored. Utterly indispensable. Even though I might use it only two or three times a month, at those times nothing else will do.
Since I first put this page up, several people have written me asking where I get my pocket protectors. The ones I'm using now are cheap and vinyl and I have to change them out every month or three because they wear out or develop holes. I usually reinforce the bottom with a rectangle about 1" x 3" cut from a plastic soda bottle, held in place with package sealing tape, because the mechanical pencil's metal sleeve tends to punch through it otherwise.
Friends are working on experimental prototypes, one using leather, another thinking about titanium.
Any decent office supply store should carry this item. Here's the information from the ones my local office supply store has:
Atlanta, GA 30324
Questions, comments?... Call 800-247-5547
Obligatory disclaimer: I have no financial interest in any of the companies named above. I just like their stuff.