Online Certificate Links

 

Via a Reddit post from years ago. If you have issues viewing the links, LMK.

Medical Terminology Certification
Boating (Maryland only)
Interpreting
Beer judge certification
SQL
National Career Readiness Certificate
American Purchasing Society certification
Haz-mat certificate

Get Ordained by Universal Life Church (+Doctorate of Metaphysics). For other cool stuff check out this hyperlink. (I did this. It's amazing :))
Get Ordained by the Church of Latter Day Dude
At the time of updating this list, this link only has a free course for ID checking (like a bar bouncer).
Canadian OSHA Equivalent and more free courses in this link.
Canadian boating courses
FEMA training
XSeries Courses (Certification Courses from Various Accredited Universities) Project Management Professional (PMP certification from PMI)
Fall Protection Awareness Training (Canada)
Google Apps Certification
Multiple certifications and courses from a college, which you can get financial aid for to make some of the courses free.
Beer server
Management and Leadership
CPR course
A Pokemon professor
Magic The Gathering Judge
Powder actuated tool certification
With Google courses
Dog Psychology and you can apply for financial aid in order to cover the cost.
Psychological First Aid and they have other clinical training programs here.
Scrum fundamental certification
Multiple certificates from HubSpot
Health & Safety UNDSS
Deputy Heart Attack
CDC lab training
Tulane University's free courses
Columbia University's free courses
NCTSN and continuing education
CCOHS courses
Colorado School of Health
Technology & Science Cognitive Class
Free Code Camp
GIS (web development and not geographical information systems)
Online Classrooms Future Learn
Coursera
Stanford
Carnegie Mellon
Open Learn
edX
Open Classrooms
A website to learn how to play guitar 

 
You can become a train conductor by using financial aid to cover the tuition costs at: Dakota Technical College, Johnson Community College, and at the Northwest Railroad Institute.
Medical illustrator, which you can go to many colleges for so financial aid can cover it
You can also become a sonographer, it includes doing ultrasound for women, but it has other applications too.
Biohazard cleaning
Being a Certified CISCO Networking Associate
Various tiers of being a welding inspector
International Air Transport Association certification for dangerous packages and transportation
DOT certification
Learning calligraphy

These aren't all certs, but some free classes/resources.
http://education-portal.com/academy/course/index.html
http://101science.com/
https://iversity.org/
http://www.openculture.com/freeonlinecourses
http://www.coursehero.com/subjects/
http://oli.cmu.edu/
http://ocw.mit.edu/courses/find-by-topic/
http://www.saylor.org/
http://www.open.edu/openlearn/
http://www.makeuseof.com/tag/3-websites-started-learning-programming-language/
http://www.flashcardmachine.com/
http://freerice.com/category It quizzes you on the basics of a subject of your choosing, and donates rice for each answer you get right once you turn off adblock
http://openstaxcollege.org/
http://freescience.info/index.php

Free books (all legal of course): novels, open sourced textbooks,

Freecycle, a site where people give away random things for free
A site to get free wood chips from
A free resumé builder
US government website to see if there are assets in your name that you can claim for money
A site to see if there are free or open sourced alternatives to whatever paid software that you are looking for.
Wikimedia, the non-profit that runs wikipedia has other useful websites.