Cogsworth - Make it easy for your customer to schedule time with you! Sync your Cogsworth to your calendar, set up your services, embed it on your website, and you're cooking with gas!
Doodle - Make meetings happen. With Doodle, scheduling becomes quick and easy.
CozyCal - Online appointment scheduling
Framadate - Make your polls
Kriya AI - Your Instant Workforce
Dudle - Dudle is an online scheduling application, which is free and open source.