TopTracker - Beautiful, free time tracking
AND CO Desktop App - A free app to track time, tasks, and run a freelance career.
timeBuzzer - timeBuzzer enables freelancers and project-driven teams to track their time at the touch of a button, understand where their time goes and create reports with just a few clicks.
FreshBooks - The ideal accounting software for small business owners.
Cattr - Cattr is a free open-source self-hosted time tracker with desktop clients for windows, mac, linux.
Clarrow - Clarrow helps you track and manage your cash-flows, create and send professional invoices, and seamlessly manage your business expenses.