Are these mods technical? The short answer is no. But the very high "cool factor" of these websites makes me think they merit a mention.
CafePress.com lets you shamelessly promote whatever or whomever you want. I love the ease of creating products to sell or give as gifts.
Another extremely cool aspect: The no-piece minimum lets you generate as much or as little promotional garbage as you want. Design and purchase just one piece of personalized underwear if you're so inclined.
You can also use CafePress.com as a storefront to sell products or buy from someone else. Let's say you're an aspiring musician. CafePress.com gives you the tools to create your own CD, case, and cover, then sell it online. You'll even get a bonus for selling your goods on the site if your base prices exceed $250. For those who love this concept and are looking for work, make a little money at CafePress.com anytime.
Minimum shipping will run you $5 and orders are delivered in five to 10 business days. Return any product within 30 days if it's not to your liking.
Here's my storefront at CafePress.com.
Running with the "personalizing" theme, CustomInk, another great option, has a custom GUI tool that allows you to design your own products.
Click "The Lab" tab for instant inspiration for putting your inner designer to the test. I really like CustomInk's color options. It offers a wider variety of colors, fabrics, and fonts than CafePress.com.
You won't get uniform prices for goods, but the site gives you instant price quotes for whatever you design. You won't get hit with any hidden charges at checkout. Shipping and setup are free. Only pay the price the company quotes you.
The biggest drawback here is the six-piece minimum for screen prints and 12-piece minimum for embroidered items. If you aren't completely satisfied, take advantage of the site's money back guarantee.