We explore modifications to the loop-induced Higgs couplings h\gamma\gamma\
and h\gamma Z from light charginos in the Minimal Supersymmetric Standard
Model. When the lightest chargino mass is above the naive LEP bound of order
100 GeV the effects are modest, with deviations in the decay branching ratios
typically less than 15% from the Standard Model predictions. However, if the
charginos are lighter than 100 GeV, more dramatic alterations to these
couplings are possible as a consequence of the rise of the one loop form
factor. For example, the diphoton signal strength can be enhanced by as much as
70% compared to the Standard Model value. We scrutinize in detail the existing
LEP, Tevatron, and LHC searches and present a scenario in which a very light
chargino with a mass as light as half the Higgs mass is hidden at LEP and is
allowed by all direct collider constraints and electroweak precision tests. The
scenario has a sneutrino LSP with a macroscopic decay length of order 10-100
cm. We outline potential search strategies to test this scenario at the LHC.Comment: 14 pages, 7 figure
