I was contacted for a Skype interview. Spoke for a half hour with my would-be supervisor. A few days later, received an email extending an offer. I asked when they needed a response by, and my interviewer said there was no deadline, and to "take my time." A couple weeks later I got back in touch to confirm I wanted the internship (I declined two other offers in the meantime) and my interviewer told me they had accepted another candidate.