If you want them to remember you, I would choose something from your hometown. Even a hat that says I heart Chicago would be nice. If you are trying to show appreciation, that really depends on the person. Typically, I buy a bottle of alcohol in these situations, but not everyone drinks. I think only one in three drink in India, so that won't always work. Gifts are very personal, so general advice might just be too generic to help.You could get toys for their kids, if they have any, or some of last years electronics. Maybe you have an old smartphone you could give? I would think it also depends on your budget. It might be they would just prefer an extra twenty dollars in tip.