High yielding epoxidation:

Trichloroisocyanuric Acid: An Alternate Green Route for the Transformation of Alkenes
into Epoxides
Mira Wengert, Antonio M. Sanseverino and Marcio C. S. de Mattos

J. Braz. Chem. Soc., Vol. 13, No. 5, 700-703 (2002)

(http://jbcs.sbq.org.br/jbcs/2002/v13_n5/27.pdf)

Abstract
The preparation of epoxides is efficiently achieved in mild conditions by reaction of alkenes with trichloroisocyanuric acid in aqueous acetone followed by treatment of the resulting chlorohydrin with aqueous KOH in ether/pentane.


The secret is use of acetone/water mixture (5:1) to produce chlorohydrins in high yield (>90%). They try various solvent mixtures and find the acetone one to be best.

Since the operative agent here is hypochlorous acid, a properly acidified bleach would probably work just as well.
Bleach contains a maximum of hypochlorous acid at pH 4 or so.

http://www.chemistryquestion.com/English/Questions/ChemistryInDailyLife/3c_bleach_cleaner.html

has a nice review of some theoretical aspects of bleach chemistry.

Hope this isn't redundant.