What if I forgot to bring my poster to the conference? Until all conferences provide digital screens, this could happen. One may leave the poster at home/office or lose it in the train. I think what to do next should depend on the value of the work and the participation in the conference, the poster content, and the conference policy.

Options:


just talk about my work
present it on my laptop/tablet screen
print it on an A4 sheet, or get a larger sheet (e.g., from a flip-chart) and draw the outline and handwrite the key parts of my poster
withdraw from the conference (no poster, no presentation), but some people may be wondering why I'm not there. 


What are the pros and cons of these options in regards to academic prestige and reputation? Usually, are there other better options?
Print it locally.

Hopefully, your conference is in a city of some non-negligible size and not in the middle of nowhere.  Find a copy shop in the city and print your poster there.

Large conferences may even have their own on-site printing, although a last-minute print job may be expensive or even unavailable.

Some people do this in any case, so that they don't have to travel with a poster.

(Your university/employer may or may not be willing to pay for a 2nd printing of the poster)