Based on a the coffee questions I've seen, it seems that hot beverage questions are in scope, so here goes mine:
We like keeping iced coffee in the fridge, particularly in the summer. It's easiest to add sugar to the entire batch, but we both like differing amounts of sugar to coffee. Sugar doesn't dissolve in cold liquid very well.
If I make a sugar suspension and put it in the fridge to sweeten the coffee as we drink it, will the mixture stay liquid or will the sugar crystals re-form? If this is impractical, can anyone offer another solution?
Edit: Here's a picture of sugar solution that we've been keeping in the fridge and using. I made it 8 days ago and it's staying in solution quite well.