Weizza, also known as Weikza, is one of the three primary paths in Burmese Buddhism, the others being merit-making and vipassana

Vipassana

Vipassanā or vipaśyanā in the Buddhist tradition means insight into the true nature of reality. A regular practitioner of Vipassana is known as a Vipassi . Vipassana is one of the world's most ancient techniques of meditation, the inception of which is attributed to Gautama Buddha...

 (insight meditation). The weizza path, is an esoteric system of occult practices (such as recitation of spells, samatha meditation

Samatha

Samatha , śamatha "calm abiding," comprises a suite, type or style of Buddhist meditation or concentration practices designed to enhance sustained voluntary attention, and culminates in an attention that can be sustained effortlessly for hours on end...

, and alchemy) and believed to lead to life as a weizza (also spelt weikza), a semi-immortal and supernatural being who awaits the appearance of the future Buddha, Maitreya

Maitreya

Maitreya , Metteyya , or Jampa , is foretold as a future Buddha of this world in Buddhist eschatology. In some Buddhist literature, such as the Amitabha Sutra and the Lotus Sutra, he or she is referred to as Ajita Bodhisattva.Maitreya is a bodhisattva who in the Buddhist tradition is to appear on...

(Arimeitaya).

Further reading

Masters of the Buddhist Occult: The Burmese Weikzas by John P. Ferguson and E. Michael Mendelson

http://viss.wordpress.com/2008/08/11/the-world-of-weizzas/

http://maungpaw.blogspot.com/2008/11/burmese-tantric-buddhism_28.html