Freshman seminar classes (like Statistics 101, for example) can have as many as 500 students enrolled. That's a lot of tests to grade, so professors often employ students within the department to grade tests. Although it's grunt work, the workload is generally spread out based on when the tests are, leaving lots of time in between for academics and extracurricular interests.
Because lawyers are seeking people who match the profile of potential real-life jurors, online jury companies ask detailed questions of applicants. You should never disclose your Social Security number or credit card or banking info. Companies typically pay $10 to $60 to online jurors. Since most online jury companies won’t need a lot of jurors, signing up for multiple companies gives you a better chance of getting picked for “jury duty.”
Attorneys preparing for trial often create a mock jury to get feedback from individuals similar to those who may eventually sit on a jury. Since it can be costly to do in this in person in the community where the trial, cheaper online jurors are the logical alternative. They might listen to audio and view video presentations, or read the material and answer questions.