For those who go straight-to-comments on HN (myself included):<p><i>Users first play a series of games with cartoon spiders, which start out as cute and harmless-looking but gradually become more realistic.
One early task involves helping a spider hide in a slipper while someone is using a vacuum cleaner.</i><p>You're also missing a spider in a top hat.
NICE (the UK "death panel") has guidance for computerised CBT. It's interesting reading.<p>It's surprising how effective a short bit of work can be to overcome quite deeply entrenched phobias.<p><a href="http://www.nice.org.uk/guidance/TA97" rel="nofollow">http://www.nice.org.uk/guidance/TA97</a>