The Mishna (Kiddushin 1:1) tell us that one can acquire a wife through money (kinyan), documents (shtar) or biya (intercourse). The first two are commonly used to buy and sell regular objects, but could one acquire objects through biya, either with the owner or with the object itself?
Look at the Mishnayot a few after that one:
נכסים שיש להם אחריות, נקנין בכסף ובשטר ובחזקה.
[Land] is acquired through money, documents and [usage].
Examples (given by Bartenura) of the "usage" technique for land include plowing the land, locking the opening, and building a fence.
Additionally, you can find that:
עבד כנעני נקנה בכסף ובשטר ובחזקה.
A Cannanite slave is acquired through money, documents and [usage].
Examples (given by Bartenura) of the "usage" technique for such a slave include tying the master's shoes, carrying his belongings, and bathing him.
Of course, the only object that Biah could be done with is a human woman, and the only time one buys a woman is as a slave. Indeed the Talmud (Kiddushin 22b) wonders whether or not a maidservant can be acquired through Biah, concluding she cannot as she also benefits from the Biah so it can't be considered using her for slave labor.