On our meanderings through the Realms of the Haunting, we come across various Carpets and Rugs. While carpets in general have various functions, reaching from purely decorative implementation to more practical purposes such as insulating a person's feet from cold surfaces and reducing sound from walking, some of the carpets in the game also appear to have magical qualities.
In the Mansion's Study, there's a long and intricately-woven carpet extending from the pedestal with the Sarcophagus to the opposite wall with Florentine's painting. According to Rebecca, this rug has some sort of device, an icon, woven into it. Judging by the residual, though clearly perceptible power radiating from it, it was supposedly used for magical rituals. This hypothesis is further invigorated by the fact that the rug's weave contains silver and gold, precious metals which were preferably used in the conjuration of demons. We could also argue that the rug has teleportative properties: when using Florentine's Staff on the Tower Gate in the Observatory, we end up right on the icon of the rug.
Adam: This is intricate. Look at the work in this.
In the Basement of the Mansion, just before reaching the Caverns, we're being attacked by several axe-wielding Lopers which are immune to our arsenal of weapons and can only be defeated by using the zone marker and squashing mechanism at the foot of the staircase leading down into the basement. Fortunately, there's a magically imbued rug whose weave incorporates a safety device, apparently symbolized by the red pentagram in the centre. As such, the rug serves as an isolational oasis of sorts, providing us with temporary protection from the inimical creatures, as they cannot enter its restrictive confines.
Adam: There's some sort of arcane design woven into this.
Charles Randall's Vicarage: LaboratoryEdit
In the basement of Adam's father's old vicarage, there's a make-shift laboratory of sorts, that may have been by Belial for some time. Apart from various chemistry apparatuses and bookcases attesting to somebody's study cases and experiments, the the room also features a worn-out, blue rug with a white pentagram, the purpose of which we can only speculate on (conjuration, safety device).