Solution: The Alchemist's Workshop

Written by Tom Weisswange

At any given time, the periodic table shown by clicking "succeeded" differs from a correct periodic table (such as the original version of this one, at http://pearl1.lanl.gov/periodic/default.htm) in the entry for one particular element. Which element was so altered varied frequently throughout the course of the hunt (the cron job to do this has since stopped working), in the following cycle:

1. Au (gold) replaced by Wr.
2. Ag (silver) replaced by On.
3. Fe (iron) replaced by Gn.
4. Hg (mercury) replaced by Um.
5. Sn (tin) replaced by Si.
6. Cu (copper) replaced by Nw.
7. Pb (lead) replaced by Ts.

Solvers could assemble this list by checking the link "periodically," as instructed. There is also a double-check that the list is complete and in the correct order, for the more alchemically inclined solvers: The changed elements are exactly the seven ancient metals, ordered by the standard correspondence between the metals, the ancient "planets" (the sun, the moon, Mars, Mercury, Jupiter, Venus, Saturn), and the days of the week (the sun <-> Sunday, the moon <-> Monday, Mars <-> Tuesday, etc.).

The altered chemical symbols spell out "Wrong nums in wts." Each element with an altered chemical symbol had an atomic weight which was incorrect in one digit. The erroneous digits, in order, formed a seven-digit phone number, which at the time of the construction of the puzzle was the phone number of a local Sbarro restaurant (unfortunately, this changed without our knowledge shortly before the Hunt started). The solution is thus SBARRO.