Although many people cannot accept Tomiki's Aikido with a competition flavour, this style is practised a lot in the USA. If you like atemi waza, you will find alot of atemi in this style especially during randori. Atemi is used to throw someone or to create an opening for other techniques. Tomiki Aikido is also called Shodokan Aikido.
Find here a clip http://www.youtube.com/watch?v=8etlpBbC6o4