I often daydream about this and it basically has formed two types.
1. Go back to observe/record some historic event. Without interferring. Being a studier of military history it is usually some battle we have little or no record of or something much debated. The hard part being how to do it without getting killed myself.
2. Go back to prevent some misfortune to someone that is calculated not to change subsequent timeline in detrimental fashion. Usually single individuals (ie. preventing a accident/murder or trying to intervene with someone to prevent a suicide.
1. Go back to observe/record some historic event. Without interferring. Being a studier of military history it is usually some battle we have little or no record of or something much debated. The hard part being how to do it without getting killed myself.
2. Go back to prevent some misfortune to someone that is calculated not to change subsequent timeline in detrimental fashion. Usually single individuals (ie. preventing a accident/murder or trying to intervene with someone to prevent a suicide.