I've picked up 4 older, out-of-print sticks (relatively cheaper than brand-new but PS2-branded for my needs) and modded 2 of them with new joystick parts and pushbuttons. The result?? Durable, arcade quality controllers with much better response times and less wearing on the hands than the original stock controller. As of right now, USB converter connections allow the sticks to be used on PS2 or PS3 or Mac and PC.
They've been electrically modified so that parts are far easier to swap out and replace in case of wear and damage. This is the first time I've done soldering in my life and I'm glad the original stick manufacturer put in such big contacts points to solder wire to and that none of the original stick PCBs have burned! Later in the year, when a new universal PCB (UPCB) becomes available (probably from a UK electronics hobbyist), at least 3 of the sticks will be modified so that they become compatible with 6 different systems (Mac, PC, PS2/PS3, and Sega Saturn/Dreamcast).
The other thing I've done is spray paint 3 of the bases in colors that are frankly more vivid than the original flat black bases. I've assembled and put on new artwork I've scrounged from the web for the faceplates. Result? Themed sticks featuring barbarian queens (Red Sonja vs. Wonder Woman), anime characters, and, soon, perhaps Mickey Mouse!
I've felt a bit guilty that I haven't used much American-style art but so is the price of being a perfectionist and wanting to get a look I can live with long term. This stuff is expensive as is and it's hard to justify mediocre work.
There just aren't great sources of hi-res art for Mickey online and many of them don't feature the particular era of the character that's my favorite (1936-1938). As a consequence, I pulled out the old Pierre Lambert Mickey Mouse coffee book and am in the process of doing at least 20 color scans to collage a new background for the faceplate of the stick I'm working myself up to doing... This'll be stick #4 and likely one of the 3 modded for six systems. The fourth stick I've tentatively decided will end up being a wireless PS3-only controller.
Here's a preview of what may become the base paint job and decals for the new stick...

One of the great free fonts I've found online is a replica of the font the Disney Company uses for "Walt's signature." It's been incorporated into the side-paneling of the proposed stick base. Paint job for the base will probably be red upper top, predominantly black glossy sides with decals for white Mickey heads or white silhouette heads and the "signatures" of Mickey and Walt. I've gotta be careful on the backside of the stick because I'm going to have to drill a hole for an extra cable connection. This stick will have two connector cables for the system compatibilites. Both cables can't be connected at the same time -- that would fry the UPCB -- but they do extend the useful life and versatility of the stick.