The 2013 Interactive Fiction competition is currently ongoing: http://ifcomp.org/comp13/info.php
It has a variety of fairly short games playable online, some being parser-based (you enter a command and the world tells you what is happening) and some in other forms (e.g. Twine games, where there's a clearly marked set of things you can do at each node, CYOA-style), some puzzly and some less puzzly. Here is a brief introduction to parser-based IF if you find yourself confused.
I enjoyed:
Additionally, if you play them and have an opinion then you can sign up and vote afterward :-)
This is the monthly thread for posting media of various types that you've found that you enjoy. Post what you're reading, listening to, watching, and your opinion of it. Post recommendations to blogs. Post whatever media you feel like discussing! To see previous recommendations, check out the older threads.
Rules: