Russian software developer Mikhail Svarichevsky needed a a PCI-E x1 video card as all of the other PCI-E slots were occupied on his motherboard. PCI-E x1 video cards are available but can be pricier than PCI-E x16 versions so Mikhail used a rotary tool with a diamond cutting wheel to remove a tab from the circuit board of his x16 card to fit the x1 slot.
At first the operation didn't work as PCI cards indicate their size by shorting specific pins -- after researching which pins he needed to short Mikhail made this change and the hacked video card ran smoothly and has continued to run for over a year now with no problems.
This is one of those tricks you hope to never have to use, especially since the cost of PCI-E x1 video cards have come down in price since Mikhail originally cut his card, but it's useful to know just in case. See the source link below for more photos and a more detailed walkthrough of the process.
Upgrading videocard. Using a diamond cutting wheel. [Mikhail Svarichevsky via Hack-A-Day]