Writer Beware® [sic] on bulk agent query services.
True story: Back when I was querying, I considered writing my own version of one of these. It would’ve been rad cool–thought then!me–with a list of agents, a list of “query components” (pitch, bio, synopsis, first n pages, etc.) which I could click-click-submit into a handy dandy email, pre-formatted and ready for sending.
I never did end up writing this, mostly because I got hung up on which MVC framework to use, then realised Mavericks had blatted my AMP stack, so got bored of the exercise and went back to, yanno, editing the book–specifically, rewriting the opening–which turned out to be infinitely more productive.