For amateur voice actors, re-dubbing movie clips has become a huge pastime and tool for practicing. It's now very popular on YouTube and similar sites. (I have an account on YT for that purpose, which I've named "notmanning.") Most recently, I worked with about 6 other dub practitioners to put together a full-length re-voicing of The Lion King. The URL is YouTube - LionKingFullFandub's Channel. I do Banzai, Pumbaa, Rafiki, and Scar. (Yes, all of them.) Check it out if you have 90 minutes to kill.