Here's one you can play with: @NostrAIDVM You send it sats and it can do stuff for you via DMs like generate AI images. Others like the ones in the note discovery tab on Amethyst that @Gigi posted are free.

There's different kinds of DVMs. The ones we see in Gigis screenshot are content discovery DVMs. They aggregate notes and apply a set of rules or filters on the notes and build a feed based on these rules. There's topic related ones, follow related ones, most zapped, most engagement in various timespans on various relays and for different kinds. This is a growing open marketplace and every client that implements nip90 can benefit from it. There might be free or paid or subscription based ones, but currently most are free to use.

Btw @NostrAIDVM technically is not a DVM but a bot that communicates with DVMs. It's an interface you can use from any client, even if they don't natively integrate NIP90 (DVMs). There's some web based clients for DVMs too and some of the social clients integrate some DVM kinds like Amethyst or Nostrudel