Here's my contribution: I have some astrologer friends that use a system based on AT Mann's time-zodiac correlations in order to pinpoint the moment in history of the humanity when we lived a significative life, related to this one
The idea is that we may have lived many many lives, but there're only a few that we are most connected to. These lives are represented in our current natal charts as planets. Their position in zodiac (the exact degree) indicates the time of that previous life. The tabel to use may be found here:
http://www.astrologyweekly.com/astrology-articles/astrology-time-zodiac.php
The main characteristics of that life may be extracted from the nature of the planet involved and also from its aspects.
Further application of this theory: in synastry, when two people who currently have a closer relationship, a conjunction of two planets (at approx. the same degree) indicates that they lived at the same time, so it is possible to identify the time when they met in a previous life.
If there're many conjunctions in their synastry, obviously that means many lives when they met.
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Another idea - the same astrologer who developped the theory above, a Romanian named Firicel Ciarnau, says that the position of the Moon in the current natal chart indicates the position of the Sun in the previous life's natal chart.
Just to mention it, his website is
www.artofdivination.com