When I'm not exploring fresh caves or lands in minecraft, I'm busy trying to find deposits of diamond, gold and iron deep in the earth. So far I've just been digging around just above bedrock on a whim to look for these rare minerals but I've started thinking that I should be taking a more controlled, efficient approach to mining.

**What is the optimal mining strategy that yields the most rare minerals while minimizing blocks removed and time spent digging and traveling?**

**Edit:** The existing answers are great for mining, but no one has addressed travel time to and from the mine which is usually ~60 blocks downward and incredibly tedious. Solutions?
['https://gaming.stackexchange.com/questions/8310', 'https://gaming.stackexchange.com', 'https://gaming.stackexchange.com/users/1070/']
In regards to getting to and from your mine:

My solution is to never leave the mine. Bring down some saplings, some wheat seeds, and whatever else, and build your base underground near your mine. It's a lot safer and more predictable than living on the surface, since you can completely light your cave system.

The only downside is that eventually your character turns pale and starts muttering about "My precious..."
Have you ever thought of getting the minions mod? Once you get it you have to get up to 8 levels of experiance (8 levels is recomended) then you press the "m" key then commit to evil in which you then pick one of three things, repeat untill you get the master staff, with it you right click the ground four times, one minion will appear wherever you right click in those four times. Once you have your four minions, you press the "m" key again and select the "dig mineshaft", once you have selected(right clicked) where the mineshaft is going to be, your minions will automaticly dig the mineshaft down into bedrock and place a cobblestone staircase. Once they finish that then you can press the "m" botton (once again!) and select "strip mine", once you have selected an area then one minion will work on it, going a certain number of blocks forward.