Decapping (decapsulation) or delidding of an integrated circuit is the process of removing the protective cover of a microchip so that the contained die is revealed for visual inspection of the micro circuitry imprinted on the die. This process is sometimes necessary in emulation projects to copy information from DRM-protected ROM chips. Particularly MAME and other arcade emulators benefit from decapping projects.
Decapping is usually carried out by chemical etching of the covering, laser cutting, or mechanical removal of the cover using a milling machine. The process can be either destructive or non-destructive of the internal die. With care, it's possible to decap a device and still leave it functional.
Decapping Groups often rely on donations to acquire hardware (ie arcade boards). CAPS0ff is the probably the biggest decapping group. They have a Patreon where you can donate to their decapping efforts.
Other groups that do a lot of dumping of arcade ROMs (but no decapping?) are the very active group The Dumping Union. They don't seem have a blog, but all news are posted on MAMEWorld (look for DU in the title). They accepts donations from PayPal. Another one is Team Europe, who also accepts donations from PayPal, see info here on how to donate.