UProc for Sheets - Boost your sales, marketing and IT tasks from Google Sheets
TrackingSuite - TrackingSuite is an all in one leadgen, website auditing , seo , crm prospecting tool.
Sheetlist - Discover free Google Sheets for marketing, finance and more
Mattermark in Salesforce AppExchange - Automatically enrich leads in Salesforce with Mattermark
Prospectss - Find leads and verify emails for free
YTMonster.net - Increase your YouTube views, subscribers, likes, and comments for free. YTMonster is the leading exchange platform for YouTube.