Zeffy for Free Events/RSVPs

Tip: we've had a lot of success using Zeffy for registration, RSVP tracking, and communications for FREE events in addition to paid ones. We always get at least one donation by allowing registrants the option to contribute. Having our attendee list on Zeffy makes communications (automated and manual) really easy, and it adds supporters to our CRM. We also really like having the record of correspondence associated with an event.

TL;DR: Zeffy is phenomenal for managing free events (and you might get optional donations anyhow!)