Konflist - Curated list of tech conferences all around the world!
Event Hunt - Startups and Tech Events Curated By Locals
TechEvents.co - Tech and startup events aggregator
All Design Conferences - A list of all front-end and design conferences
Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
Leade.rs - Leaders matches event organizers with speakers in tech.