You can buy a kit to inject an RFID chip under your skin

From — what we've been clamoring for since the Bronze Age — a special marking to gain entry to locked doors and to purchase goods and services.

From Αποκάλυψη του Ιωάννη:

καὶ ἵνα μή τις δύνηται ἀγοράσαι ἢ πωλῆσαι εἰ μὴ ὁ ἔχων τὸ χάραγμα, τὸ ὄνομα τοῦ θηρίου ἢ τὸν ἀριθμὸν τοῦ ὀνόματος αὐτοῦ. Ὧδε ἡ σοφία ἐστίν· ὁ ἔχων τὸν νοῦν ψηφισάτω τὸν ἀριθμὸν τοῦ θηρίου· ἀριθμὸς γὰρ ἀνθρώπου ἐστί· καὶ ὁ ἀριθμὸς αὐτοῦ χξϛʹ

Images: Dangerous Things

[via Core77]