The tabernacle is to be situated "in churches in a most worthy place with the greatest honor." The dignity, placing, and security of the Eucharistic tabernacle should foster adoration before the Lord really present in the Blessed Sacrament of the altar.
The sacred chrism (myron), used in anointings as the sacramental sign of the seal of the gift of the Holy Spirit, is traditionally reserved and venerated in a secure place in the sanctuary. The oil of catechumens and the oil of the sick may also be placed there.
Source: Catechism of the Catholic Church (Vatican.va)