First Things First was nominated for an XYZZY award for Best Game, and won Best Puzzles, among others.
In this game that starts out very slowly, you quickly progress to an interesting situation similar to A Mind Forever Voyaging or Lost New York, where you can investigate a mid-size map over 50 years using a time machine. Your actions in certain time periods strongly affect the future in interesting ways.
This is definitely the best long-form time travel I have played, as I felt Lost New York (which explores New York over a century or two) and Time: All Things Come to an End (which explores many epochs in a linear fashion) had relatively unfair puzzles.
IFDB has version 3.0, but the walkthrough is for 1.1, so it didn't work in places. I am a walkthrough junkie, so it was hard for me to beat it, but I was able to guess from the walkthrough what I should try next, and eventually worked my way through it.
The game has good characters, beautiful settings, and a bit of a confused plot, which is natural given the main gameplay mechanic.
For simulation fans, it has an interesting money/bank account/investment system.
Strongly recommended for everyone. (Note: the first area seems incredibly boring, but it gets better and better. I started to like the game as soon as I made it into (Spoiler - click to show)the garage.)