Electroporation is a powerful alternative to heat shock for delivering small molecules such as plasmids across cell membranes. By application of an electrical field netivetly charged DNA is forced into elector-competent cells by an electrohoresis-type effect. Electroporators can be expensive, generally over $2000, hence the popularity of more chemical solutions such as heat shock.
Enter the ElectroPen from the Bhamla Lab at Georgia Tech. Which can be very effectively advertised in one chart:
Bhamla Lab put up all this information in one massive twitter thread, and you can read through the whole thing in a slightly more reasonable format on threadreaderapp.