Getting their attention

I've been thinking about the best way to get children's attention in class. I've tried lots of different things before, guess it's just a case of finding what works for this class but I don't want to do clapping anymore, I don't like it really. So I posed the question to Facebook and Twitter and here are some of the responses.

• I sing 'are you listening' or 'are we ready' and hopefully they reply 'yes we are'
• Whistle
• Count down from 5
• Rainmaker
• Bells - shake them and get children to put their hands in the air
• I clap 3 times, they copy and put their hands on their head so I know they're listening. Points to the first 3

Here's a picture from Pinterest too:

Quite like the idea but not sure I want to use my voice to stop them, especially during group work! Maybe clapping is the best way to stop them AND save my voice! Maybe if they class got used to the clapping from the start and I make sure they do something like put their hands on their head it'll work better.

Still looking for ideas, any more suggestions?