As I've mentioned, I have been playing Fallout 3 a lot lately.
One thing I haven't mentioned is that I really like one of the minigames in it. For those who don't know, in videogames a minigame is a small, relatively simple game contained within a larger one. It usually focuses on a subsystem within the game, and is often puzzle-like.
Fallout 3 has two primary minigames. The first is to represent lockpicking. It isn't that exciting. It is a visual representation of a lock into which you insert a bobby pin. You move the pin back and forth to find the sweet spot (the size of which depends on your lockpicking skill and the lock's difficulty). Ideally, you do this without breaking too many bobby pins first.
The second minigame is the fun one. It is a logic puzzle used to represent breaking into a computer system. You get a monitor full of gibberish out of which you try to pick the admin password. There are a bunch of words in there. You get four attempts to get the right one. If you guess wrong, it will tell you how many of the characters in the word you picked were in the right place. You can also look for particular character strings that will remove some wrong words or replenish your attempts.
What works about this? Well, first, it is a logic puzzle - and I like those. It also does a decent job of thematically representing computer cracking - and uses skills that aren't wholly unrelated to it.
I see a lot of minigames in video games. Some are done well. Many aren't.
What I haven't seen are a lot of minigames being used by GMs in tabletop RPGs. I could see minigames being used in a variety of places - to replace things that might be drudgery such as (depending on your players) mapping out a labyrinth or bargaining with a merchant or to replace things that are normally decided by a die roll, but to which you might want to add a bit of extra tension such as disarming traps.
If you do this, I'd make two suggestions: (1) tie the nature of the minigame to the task it represents and (2) don't divorce the minigame from the PCs' abilities. As an example, I could see using a Jenga minigame to represent disarming a trap. In a d20 game, I might say that the pulls from the tower take the place of a d20 roll with each pull that occurs before the tower falls adding one to the player's disable device total. Another example? You want to see how accurate a map of the dungeon the PCs can come up with after having run through it quickly? Deal out 10 or so (possibly depending upon an appropriate intelligence-type check) playing cards face up, then quickly flip them over one by one. Have the players arrange them in numerical order from highest to lowest without peeking (based on their brief glimpse). Look at the order they put them in, but don't show it to the players. Now draw the map with one error for each out of place card and hand it over to them.