Startup Asylum: You’re right where you should be! I may be a tad bit biased though.
MaterialUp: Daily material design inspiration.
FLTDSGN: Daily showcase of the best flat UI design websites and apps.
Site Inspire: Web design inspiration.
UI Cloud: The largest user interface design database in the world.
Moodboard: Build a beautiful moodboard and share the result.
Crayon: The most comprehensive collection of marketing designs.
Land-Book: Product landing pages gallery.
Ocean: A community of designers sharing feedback.
Dribbble: Show and tell for designers.
Behance: Showcase & discover creative work.
Pttrns: Mobile user interface patterns.
Flat UI Design: Useful Pinterest board.
Awwwards: The awards for design, creativity and innovation.
The Starter Kit: Curated resources for developers and designers.
One Page Love: Resource for one-page website inspiration.
UI Parade: User interface design tools and design inspiration.
The Best Designs: The best of web design.