I usually try and incorporate information from the time of day into my roleplaying, which means I can find convenient reasons to be somewhere at 3 PM local time ICly. Weather is also nice and provides fodder, but most of the time I'm fine with providing my own if I'm outside and nothing is specified.

If I'm inside and my character is watching TV or something, time might determine what's on. Either news, primetime programming or whatever it is.