OK. I've seen these all over scratch, and always wondered how to get them. Well, I figured it out! But not for all - here is a list of some Unicode Characters that you can copy and paste. NOTE: You may not be able to see them because you don't have Unicode installed.
Weather and Outside - ☀ ☁ ☂ ☔ ☇ ☈ ☉ ☼ ☽ ☾ ☃
—–
Space - ☄ ☆ ★
—–
Death/Life - ☠ ☢ ☣ ☤ ☮ ☯
—–
Genders - ♁ ♂
—–
Checks and Crosses - ☐ ☑ ☒ ☓
—–
Pointing Fingers - ☚ ☛ ☜ ☞ ☟
—–
Chess - ♔ ♕ ♖ ♗ ♘ ♙ ♚ ♛ ♜ ♝
—–
Smiley Faces - ☺ ☻
—–
Telephones - ☎ ☏
—–
Miscellaneous - ☊ ☋ ☌ ☍ ☕ ☖ ☗ ☘ ☙ ☡ ☥ ☦ ☧ ☨ ☩ ☪ ☫ ☬ ☭ ☰ ☱ ☲ ☸ ☹ ☿ ♃ ♄ ♅ ♆ ♇ ♈ ♉ ♊ ♋ ♌ ♍ ♎ ♏ ♐ ♑ ♒ ♓
—–
Any other major ones I'm missing, or do you have several minor characters? I'll add them if you comment with them.
Here is a large list of them - possibly all of them.

Unicode Table (Thanks XGamer01)
Some Text Faces (Thanks Dreamo)

Bump

This has all most of them.

There's also some neat text faces made from Unicode characters characters on this website.

support ☑

Mega_Guy wrote:

support ☑

For what?

How did you do it?

XGamer01 wrote:

This has all most of them.

That has all of them since it is the official Unicode table, although it's a bit slow to look through.

On Windows, you can also go start > Programs > Accessories > System Tools > Character Map, although you have to look through all the fonts because they each have different symbols.

http://graphemica.com/%F0%9F%92%A9 :

On mac, you can press CMD+CTRL+SPACE and click the little symbol in the top-right corner of the little box that pops up to get all symbols.

XGamer01 wrote:

This has all most of them.

I use that