Right. Beat this.

*cracks knuckles*

103.9p per litre = $2.04
£3.93 per gallon = $7.73

Just looking back through past prices, it looks like the dollar's a bit stronger than it was last time I posted. At it's previous strength (take my last post, for example), one gallon at 103.9p per litre would cost us about $8.04.