I often run into situations where I want to schedule a meeting with someone, but don't want to go through the hassle of configuring a professional appointment scheduling tool (such as doodle.com). The idea of cal.tf is to email a link to your calendar (such as my.cal.tf/ajfb429j) and the recipient can simply pick a time where you're free and reply with their desired date/time via email or IM. This makes it easy for the recipient (because they don't have to sign up for anything) and you, because you don't have to put your availability in writing, which is always awkward.<p>In Google Calendar's built-in sharing options, you can only select "Share via email", where the recipient then has to import your calendar into his/her own Google Calendar (so this is meant as a more permanent solution, not for quickly scheduling a meeting) or make your calendar completely public (which will lead to it showing up in Google search results!).<p>On cal.tf, you can choose whether to show the full event titles or just "Busy" indicators on your public calendar, and the sharing link is long enough to make it hard to guess.