This site is an amazing one for listening skills, learning vocabulary and practising pronunciation. It has a really wide range of video material at different levels, (indicated easy, medium and hard) that you can listen to and transcripts below them so that you can read along as you listen. That in itself would be helpful, but this site goes a whole lot further! As you watch each video, you can go back a line at a time and listen again (helpful), you can slow down the speed of the speaker (very helpful - I particularly love this feature) and you can click on the more difficult vocabulary in the transcript and it will give you a definition and a pronunciation guide (how much help do you need?!!). Fabulous! There is such a wide range of material it should appeal to adults with a wide range of interests and to young learners. You can register on the site and it will keep a track of your scores, but you can also use it without registering, and in either case it's free.

After you've watched the video, you can also use a microphone to record yourself reading each of the lines and the site gives you a score. Most of the videos have American accents, so you won't get 100% scores if you don't mirror that, but it's quite forgiving of other accents and even when I put on my most RP voice (ie quite different to an AmEng accent, but perfectly acceptable) it gave me a high score.
I think that this is something that you could set as a homework task, allow learners time to listen, understand the vocabulary, practice some of the pronunciation, and then come to class prepared to discuss a video that they have watched. It may be that you want to give them all the same one or they could each choose one and describe theirs to a small group as a jigsaw activity.
Limitations - I'm stuck to think of any!