Tabmeter
I see my Chrome new tab page about 200 times a day. It's useful space that goes unused—or worse, has ads. Windows had Rainmeter for desktop customization, but browsers had nothing comparable for developers who wanted real utility on their most-visited page.
TabMeter is a Chrome extension that transforms the new tab page into a customizable widget dashboard. The core challenge was building a flexible widget system that's both powerful enough for complex displays and simple enough that adding a widget feels effortless. I opted for vanilla web technology to keep the barrier for entry for new developers as low as possible (Rainmeter was one of my very first introductions to programming as well.) Plus, instant load times are vital for the new tab page.
Code generation tools are very good at building widgets, and you might find them impressively capable of styling if you provide a descriptive style guide. Next iteration will include a widget marketplace and better configuration persistence, but the core premise has proven itself.
