I love stories of user-driven innovation. Here's one I just discovered: the Magic Lantern firmware upgrade for the Canon EOS 5D Mark II camera. Trammel Hudson tells the story of his elegant and vital hacks:
More awesomely, at 08:11 in the video (and here on the Wiki) Trammell tells us that his software is "free-as-in-speech GPL". Watch the video to see just how many pro-level features Magic Lantern provides to make the EOS 5D Mark II a more professional-level HD video camera. With a little DIY LEGO action, even follow-focus is possible! Of course Trammell's own approach (hacking the bluetooth interface, shown briefly in the video) is more elegant. This should further validate the importance of making things user-modifiable, and preserving the legality of user-driven innovation.
I've been resisting the temptation to upgrade my EOS 5D (Mark I), but this might swing the balance for me.