I've read the johnson & johnson covid vaccine works/was designed a bit differently than the other two that are available. how is it different? is it more like the vaccines we're used to (flu, etc.) in terms of how it is made?

The difference in not particularly relevant. J&J vaccine has the Covid nucleic acid incorporated into a harmless adenovirus that helps in immune response. Moderna and Pfizer have a segment of the viral RNA that codes for the spike protein that is essential for the virus to gain entry into human cells. Get the vaccine, any vaccine. all will protect against serious illness due to Covid.

J & J made a “viral vector vaccine that uses a weakened live pathogen (adenovirus) as the delivery method (vector) for transporting a recombinant vaccine for COVID-19.” REF: https://www.verywellhealth.com/johnson-and-johnson-covid-19-vaccine-5093160. Pfizer & Moderna are mRNA vaccines. Bottom line, would take it if offered – it could save your life.

I will be redundant, and echo my two esteemed colleagues. Does not really matter which vaccine, as there may be little opportunity to choose. If your name comes up, get it ASAP. Do not delay, as millions of others wish to be vaccinated.