While marketplaces like Fiverr and Freelancer.com are geared towards freelancers, Remote OK (remoteok.com) is a job board to search for full-time remote job opportunities. What makes Remote OK stand out is their fee of 549$ for posting a job.
This ensures that only serious employers post their jobs here. For remote workers (free joining), this saves a lot of time as they need not waste their time applying fake job posts.