Green Eyed

O, beware, my lord, of jealousy;
It is the green-ey'd monster, which doth mock
The meat it feeds on. That cuckold lives in bliss,
Who, certain of his fate, loves not his wronger:
But O, what damnèd minutes tells he o'er
Who dotes, yet doubts, suspects, yet strongly loves!

My friend Craig had an eye test where they introduce a fluorescent pigment which makes for a startling effect!