GitHub Repository Size - Browser extension to show file and repo size in GitHub
Awesome GitHub Topics - Top 500 topics on GitHub that's filtered and categorized
GitNews App - Trending repositories from GitHub, HackerNews & Reddit
git:logs - The definitive list of open source resources on Github
Roundup - Email digest of new releases from your starred GitHub repos
Mailbrew - Automated email digests from Twitter, Reddit, YouTube & more