Twilight Heroes

From the publisher:

Twilight Heroes is a FREE, browser-based superhero role-playing game.

By day you're an underpaid and unappreciated worker at a pain-in-the-neck job, but as the sun goes down you don a mask and a cape and patrol the streets in an attempt to clean up the crime-riddled and corrupt city you live in. Sure, your first weapon is a household tool and your costume is made from home-dyed pajamas, but fighting crime is about delivering justice, not being stylish.

Along the way you develop super powers, such as amazing strength, mastery of the elements, or the ability to manipulate things with your mind. As you grow in power you acquire more skills and items, and face an increasingly challenging series of goals, quests, and super-villains. You can choose from powerful talismans to channel your abilities through, and build a secret base to use as your hideout and refuge when you're not fighting crime. Just don't stay up too late, or you might have to face consequences the next day at work.