Tattoos are man's oldest and boldest expression of creativity; unfortunately, they're also man's oldest and boldest source of hepatitis C. Exercise that same expressiveness on your clothes: Hard Rider NYC.
HR's run by Queens native Frank Rinaldi, a former marine who custom inks original, tattoo-inspired designs on tees, hoodies, long-sleeved shirts, and tank tops (tempting for gun-showers, though they preclude a blazingly original silkscreen barbwire armband). Visit the store, and Rinaldi will break out his binder of fabric-tats, then help you choose the number, size, and placement on your garment; you can opt for a single jobby, or go for a multi-graphic'd kaleidoscope of badassery/technicolor dreamcoat of...dreams? Designs range from the stylishly medieval (sword-crossed, HR-logo'd shields) to biker-core chic (iron cross/steel wheels), to some too hardcore for anywhere but prison or 7720 Queens Blvd -- though inking "Sik Fuk" on your hoodie is a great way to distract from the Bright Eyes shirt peeping through your zipper.
Custom work's all performed on site, but if visiting a biker den of iniquity makes you nervous/lazy, you can order pre-made designs online -- the sartorial equivalent of ordering a buttock pre-inked with "Bernice-4-Ever".