Useful Math Sites and Resources. Courtesy of http://webchat.snoonet.org/math

General Resources
www.texpaste.com/ | Great bin with Latex for sharing problems
www.copypastecharacter.com/mathematical | List of math unicode for easy in-chat copy/paste
www.twiddla.com/ | Free no-login collaborative whiteboard with latex.
www.wolframalpha.com | Advanced math calculator software.
en.wikipedia.org/wiki/List_of_mathematical_symbols |For easy copying/pasting.
https://github.com/ystael/chicago-ug-math-bib | Book recommendations.

Math websites and blogs
http://tutorial.math.lamar.edu/ | Paul's Online Math Notes.
http://mathinsight.org/ | Site focusing on Underlying concepts/theories in math
http://terrytao.wordpress.com/ | Mathematician Blog.
http://blog.tanyakhovanova.com/ | Another Mathematician Blog

Math Help
http://math.stackexchange.com | Math Question and Answer website.
www.reddit.com/r/cheatatmathhomework | Reddit Q&A Subreddit.
www.reddit.com/r/mathhelp | Another Reddit Q&A Subreddit.
http://mathhelpforum.com/ | Traditionally formatted Q&A forum for math help.
www.freemathhelp.com/forum/ | Another one.

Math Textbooks and Text-based Courses
http://www.people.vcu.edu/~rhammack/BookOfProof/ | Introduction to proofs and logic
http://www.math.brown.edu/~treil/papers/LADW/LADW.html | Linear Algebra
http://people.math.gatech.edu/~cain/notes/cal1.pdf | Multivariable Calculus
https://www.reddit.com/r/mathbooks/ | Resource for free & legal math textbooks

Online Courses and Videos
www.khanacademy.org/math | Extensive videos and interactive math problems.
www.coursera.org/browse/math-and-logic | Free online courses. Most scheduled
www.edx.org/course/subject/math | Free online courses. Some scheduled.
http://ocw.mit.edu/courses/mathematics/ | MIT Open Courseware for Math.
www.youtube.com/user/patrickJMT | Great youtube channel for problems.