[Mac OS X] Creating encrypted, password protected folder (no additional apps)

We all have files we don't want other people to see. It may be porn that you don't want you parents to find, or naked pics of your gf/bf that your friends could find interesting or it may be file with passwords, keys, licenses that you want to keep for yourself. There is very easy way to do this in OS X. You just have to create encrypted disk image using Disk Utility and use it as normal folder. Here is step by step instruction:

1. Open Disk Utility. It should be in Applications->Utilities or just use Spotlight

2. Click on "New Image" on top. Give it proper name and choose where you want it to sit. Chose size and encryption, I would recommend making it bigger that you think it will have to be since there is no easy way to change size later (or I just missed it :P).
3. When you hit create it will ask you for password. If it didn't you probably missed setting encryption settings. Remember that checking "Remember password" might not be the best idea — folder will be encrypted BUT if anybody get to your computer they will be able to open file. Also for good passwords, your password assistant. It can generate memorable, secure passwords.
4. Wait.
5. After a while your folder (disk) should be created. After you go to finder and double-click it, it will appear in sidebar in devices section. To open it, click on icon in sidebar. You will be able to access folder without giving password until you Eject it, just like you would do with USB drive. And if you don't care about possibility of destroying all data stored in USB drive and you don't know how to eject it then you this little icon on right: ⏏
Hope you find it useful. If you do it then you can put such disk on DropBox since it was encrypted on client, nobody will be able to access it :)