It's interesting for presentations
Skype is a tool that we have used at school since 2011 year, when we bought interractive board.
-because it is so easy and gratful for working with students
Twitter is a tool that I present my students in 7th and 8th class at our Informatics and Computer
OneDrive is very powerfull tool for saving our files - pics, Excel worksheets, Word documents, PD