You can make your Skype conversations a lot more fun with an application like All-in-one Voice Changer. This is a real-time voice changer that allows you to fake and modulate your voice in real-time, as you are talking.
A simple voice changer in real-time
This program runs in the background while the app you are using for, say, a voice call, is running. It simply registers the incoming voice on the PC microphone and modifies it. It offers different voice profiles for doing this: dinosaur, man, woman, cat... It also allows users to save the audio recording.
The program is stunningly simple, which means that it can come in handy for having a bit of fun, but for little else. If you were thinking of something more versatile, perhaps for your videogames, it would be better to try out Voicemod. In addition, All-in-one Voice Changer will not prove useful for audio projects that require a certain level of professionalism (recording podcasts, voice-overs, and other tricky stuff). But, hey, if what you are looking for is something simple for your voice calls then this program is perfect.