245i was the last amnesty.
It applied to people who where illegally present on dec 21 2000 and had a labor cert or marriage filed before 4/30/2001. Immigrants who fulfill both conditions are able to adjust status even if they are presently illegal, worked without permission etc.
Some of these cases are are still in the pipeline. Many of the labor certs filed on 4/30/2001 (several hundred thousand, state labor offices had literally containers full of petitions on that day) took over 4 years to be approved. Right now they start to get into the adjustment phase and contribute to the scarcity of visa numbers.
And while in the case of successful 245i adjustment, all past misdeeds are forgiven, traveling before obtaining the green card can lead to a 10 year ban on re-entry into the US. If you never had illegal presence, all this discussion about the 3/10 year ban doesn't apply to you.