Reddit List - Tracking the top 5000 subreddits
Groouply - Track keywords on Facebook groups
Reddit Check - A tool to check if a URL is on Reddit and going viral
UpvoteTracker - Track the upvote history of Reddit and HN posts
Suggest Subreddit - Recommends you subreddits based on your subscriptions
Notikey - Get notified when your keywords are mentioned on Reddit