Alternia is the beginnings of a mod similar to stuff like Altoholic; it's an addon to track stuff across alts. Right now, all it does is items and currency. Here's how it works:

1. Log in.
2. Do anything that affects your inventory on a given character.
3. You will now get tooltips for items showing that character's inventory of them.

So, say you log in on a forager named Jack and have 90 mahogany. When you log in on someone else, and get a tooltip for Mahogany, you'll get a little box above it saying "Jack: 90". Your own inventory is shown as "Bank: ##" and "Inventory: ##", although that hasn't mattered much for most purposes (like crafting) in a long time. Currencies work the same way. However, coins are magical because they show no tooltips, so you have to get that some other way, like "/alt -c coin". Credits are untracked; the game reports them as a currency, but that's useless because they're not per-character. Currencies which are account-bound (tradeable only with vouchers) will show up only for alts on the same account. 0.7 added "/alt -l" to see current levels, percentage of XP obtained, and PA levels, and also picked up a slight fix for the inventory tracking to handle the bank vs. vault distinction.

If you use more than one account, you have to flag each character whose inventory you want seen regardless of account; log into them and do "/alt -s" to toggle inventory sharing.