List of NLP challenges Is there any comprehensive list of past, current and future NLP challenges?

E.g. for NLP conferences, Joel Tetreault's unofficially official conference calendar and WikiCFP are pretty good.

The "Competitions and Challenges" page on the ACL wiki quite incomplete.
List of NLP competitions on Kaggle by popularity [number of teams]:


Two Sigma Connect: Rental Listing Inquiries [2709 teams]
https://www.kaggle.com/c/two-sigma-connect-rental-listing-inquiries   
Home Depot Product Search Relevance [2125 teams]
https://www.kaggle.com/c/home-depot-product-search-relevance   
Quora Question Pairs [2123 teams]
https://www.kaggle.com/c/quora-question-pairs   
What's Cooking? [1388 teams] https://www.kaggle.com/c/whats-cooking   
Crowdflower Search Results Relevance [1326 teams]
https://www.kaggle.com/c/crowdflower-search-relevance   
Bag of Words Meets Bags of Popcorn [578 teams]
https://www.kaggle.com/c/word2vec-nlp-tutorial   
Transfer Learning on Stack Exchange Tags [380 teams]
https://www.kaggle.com/c/transfer-learning-on-stack-exchange-tags/data   
Facebook Recruiting III - Keyword Extraction [367 teams] https://www.kaggle.com/c/facebook-recruiting-iii-keyword-extraction


New entrants are prohibited, you won't be able to download data for this competition   

Dato: Truly Native? [274 teams] https://www.kaggle.com/c/dato-native   
The Allen AI Science Challenge [170 teams]
https://www.kaggle.com/c/the-allen-ai-science-challenge