An extremely cool DNA origami nanodevice which can be induced to penetrate lipid membranes and transport/inject molecules of interest. It should be noted that the authors used artificial vesicles (not living cells) for their proof-of-concept. That said, I think the device has potential if it can be modified for robustness in biological environments.

A membrane-anchoring nanodevice that integrates reversible, fuel-driven mechanical actuation enables programmable membrane penetration, cargo delivery and spatiotemporal regulation of biochemical reactions in synthetic cells.