Maybe you should start with at least $100?
As a borderline nerd I would like to play the devil's advocate here and point out that micro(μ) scientifically according to the Système international d'unités's metric prefixes standards for 10−6 of a given unit. Since this is Bitcointalk we can assume that the default "metric" unit can be assumed to be a BTC and thus a μBTC loan would be for loans in and around the range of 0.000001BTC. Thus the lender's service is actually beyond a micro loan and nearly touches the territory of a milli loan service
Obligatory sarcasm note for those who fell for Poe's Law