An interesting side-effect of the Mail Tool is that it allows us to see the exact account creation time of a new account, since an email is immediately sent with the account's password. Since the Mail Tool has been in operation for a while now, we are able to find a trend to determine when an account was created based on the account's Slashdot User ID.

The Mail Tool has been in use since October 30, 2003, so the data here is based on information from October 30, 2003 to March 31, 2005. The data collected is only for the 132 accounts created with the Mail Tool, so this is not definitive data. However, it does appear to be a decent sampling of the full set of data.

A quick perl script fetched the User IDs of the accounts that have been created with the Mail Tool, and a linear least squares regression of the data (Unix timestamp of account creation time and account's UID) gave us the function

f(x) = 292.9945335682602 x + 856457817.2578925

A graph of the data points and the above function

This is a satisfying approximation for our purposes. So, you can take a Slashdot User ID, x, and predict the time that the account was created, f(x), within reasonable accuracy.

A final note: this function tells us that new Slashdot account is created about every five minutes.