This lets you do things like setting the key for "The Beatles" to "Beatles, The", which the Empeg software partially deals with now, but also lets you do things like setting the key for "Peter Gabriel" to "Gabriel, Peter", which the software currently doesn't even attempt to deal with (for good reason).

An old, discontinued, but unsurpassed CD player and manager DiscPlay4 from Obvion employs somewhat simplistic, but very useful trick: the user is supposed to enter author's name in the normal 'first_name last_name' order, but if you check 'sort by last name' checkbox it will sort them by the last word of the name (which usually is surname).

Separate search key is better, of course, but this trick could be used to guess its initial value.