Different cards: Lion Eye Diamond and Browbeat

I have 2 questions about those cards, which are unrelated but I can't figure out how to use both of them.
Lion's Eye Diamond: I can't find any application for that card except to use its mana for permanent or inflatable creatures. I've red somewhere that it is used to activeate Wheel of Fortune or Timetwister, since you could declare the card and use the Diamond to play it and THEN discard the whole hand, but it doesn't work here. Also, of course, it could be good for those decks that play cards directly from graveyard, but then I can't figure out how to build a decent deck around that.
About Browbeat, I just don't understand the text. Would anybody of you be so kind to explain me how it is supposed to work? It resamble me the psychological game of the prisoner, where 2 persons are in different rooms and they are asked to spoil informations. If noone does, there is the highest benefit, but what if one speak and the other doesn't?
Lion's Eye Diamond: I can't find any application for that card except to use its mana for permanent or inflatable creatures. I've red somewhere that it is used to activeate Wheel of Fortune or Timetwister, since you could declare the card and use the Diamond to play it and THEN discard the whole hand, but it doesn't work here. Also, of course, it could be good for those decks that play cards directly from graveyard, but then I can't figure out how to build a decent deck around that.
About Browbeat, I just don't understand the text. Would anybody of you be so kind to explain me how it is supposed to work? It resamble me the psychological game of the prisoner, where 2 persons are in different rooms and they are asked to spoil informations. If noone does, there is the highest benefit, but what if one speak and the other doesn't?
