Sikhism.

> Sikhism rejects claims that any particular religious tradition has a monopoly on Absolute truth. Sikhism emphasizes simran (ਸਿਮਰਨ, meditation and remembrance of the teachings of Gurus), which can be expressed musically through kirtan, or internally through naam japna ('meditation on His name') as a means to feel God's presence. It teaches followers to transform the "Five Thieves" (i.e. lust, rage, greed, attachment, and ego).

All sounds pretty cool, but I have always liked that it's one if the few that outright rejects any religion's monopoly on Absolute Truth.