Audacity is a widely used, simple sound recorder and editor. It's free to download and very easy to use. We now use it to record all our speaking assessments but it also has fun uses as well. As well as making simple recordings, effects can be added: voices can be 'chipmunked' to make them sound high-pitched and squeaky. You can add echo, wah-wah effects and many more. You can also delete unwanted bits. Audacity is here.