I issued a (valid) DMCA notice to a small corporation who used the intellectual property of a colleague but did not pay them for it (they promised payment in writing, then just… didn’t pay for a year or more). Their whole business website was down for a week or more as a result, as their registrar just took down their website without checking anything, and they didn’t really have technical staff to resolve it.

The whole DMCA system is quite a broken mess, and is often (usually?) used unethically. However, it is possible to use correctly, even by private individuals. I’d be lying if I said I didn’t enjoy it a little, that day.