Glogster

Glogster is a web 2.0 where you can create posters online. It is easy to use and to create and account, you need a e-mail account and you must write a password. All the instructions are in English.
When you are creating a poster, you can chose if it is horitzontal or vertical. You can put pictures, videos, titles... Finally, this tool can do embeds.
The website is:
http://www.glogster.com/