Hourglass saw some experimentation when it was first released, and it still sees some play. Unfortunately, its purpose is to force the runner out of clicks to give the corp some breathing room. The fact that it is strength four and out of an au naturale Yog is good for it, but it suffers from the problem all ICE does - rarely will the subroutines fire more than once. Add to that that if the runner wants to risk it, running last click makes this piece of ICE not even a tax, as the subroutines will do absolutely nothing.
It can cause some problems, and while it may be useful to stop the runner from clicking through the next piece of Bioroid ICE they encounter, positional uses are always harder to pull off and make ICE that rely on it less effective. It falls short that even when its subroutines are guaranteed to fire, it is not something that will have an effect for more than a turn or two at most, and after that just becomes a light tax, if one at all.
Ryon Knight might see Hourglass be given some use. While still a two card combo, if seen and played early enough it's a guaranteed brain damage (Unfortunately though the strength of Hourglass still leaves it vulnerable to Net-Ready Eyes+Yog.0). Combo heavy, but at least Knight also works well against runners worrying about Brain-Taping Warehouse and clicking past Bioroids.