Mailmeteor - Send hundreds of personalized emails with Gmail.

NewsWhip - Chrome extension that checks how viral your content is

GMass - GMass allows you to easily schedule emails, send out mass emails and mail merge campaigns and more with Gmail! Click here to learn about more features!

Promo Self Serve - Launch a promotion across the internet in 90 Seconds

Streak - Manage customers inside Gmail

SocialRank - Graph search for TWTR. Filter by interests, location, etc