Not sure if any of these would be of interest, but I enjoy most of them and they're usually animated duck gif free:

http://www.reddit.com/r/Foodforthought/ - Intelligent and thought-provoking commentaries on life and culture.

http://www.reddit.com/r/dataisbeautiful/ - A place for visual representations of data

http://www.reddit.com/r/MapPorn - Cool maps. Also tons of other neat similar photo subreddits in this format.

http://www.reddit.com/r/TrueReddit - Insightful articles

http://www.reddit.com/r/DepthHub - Insightful comments on other subs

http://www.reddit.com/r/subredditoftheday - Features one random subreddit of the day

http://www.reddit.com/r/trueaskreddit - A slightly less dumb version of Askreddit

http://www.reddit.com/r/wikipedia - Interesting wiki articles

http://www.reddit.com/r/IfYouLikeBlank - Find new music based on current things you like

http://www.reddit.com/r/tedtalks+ted - Listen to people talk about topics

http://www.reddit.com/r/tldr - Daily digest of interesting posts from reddit

http://www.reddit.com/r/ArtisanVideos - Videos of people making cool things

http://www.reddit.com/r/whatisthisthing - Help redditors identify unknown objects

http://www.reddit.com/r/internetIsBeautiful - Find interesting websites