As I see it, I can see back in time…thus time travel should be possible. When I look at the sun (not that I look at it, but you get the idea) the sun’s light takes about 8 minutes to reach me, therefore, I see 8 minutes into the past. If you look at far away galaxies, I suppose you can see pretty far back in time… 
The film Millenium has one good idea on time travel. A time traveler could take objects or people(FreeJack expands on other uses for these folks) the instant before they are destroyed, and replace them with the same amounts of the proper materials. Why bother with money? If you take it back to your own time, inflation renders it almost worthless. If you invest it, you run the risk of destroying the economy. But, you could empty the Library at Alexandria the instant before the books burn, replacing them with scolls and such that would leave ashes of the right kind and amount. Then, find a place to store the books so that they age. History remains intact. But in your present, you now own a fortune in ancient manuscripts. There are plenty of similiar events. History and the economy would be undamaged. But in your own time, you could produce originals by Shakespeare, Chaucer, Dickinson, Van Gogh, etc.
R A Lafferty’s Thus We Frustrate Charlemagne gives a reason why time travelers might not be noticed. [NOTE-this is more a tour of wonders than a proper story. It has no real plot and thus cannot be spoiled]Each time they change the past everyone, including them, remembers it always being that way. Their experiments radically alter the world around them. But since it seems the same to them, they consider the whole project a failure.
An episode of the new Outer Limits gives a similiar explanation. Nobody but the time traveler remembers how events were before she altered them. She, OTOH, remembers the original history and the new one. Each time she alters history, she gains a new set of memories that conflict with all the others. Obviously, this is not a good thing for the human brain.
Re-Location
Piers Anthony uses this in Bearing An Hour Glass. Some one explains to the new Time that since everything is in constant motion, his abilities allow him to move in space as well as time.
I say the whole thing depends on your definitions of the dimensions of the universe we inhabit. Do we move along 4 axis (axes? axii?)-length, width, height, and time? Or is time simply an aspect of each of the other three? length in space/time, width in space/time, and height in space/time? If time can be viewed as a line, do other lines intersect with it? EG At the exact instant of 9 am EST today, an interval too small for even the fastest and most precise devices to register, did another reality interset with our own? If Time/space began in the Big Bang does that mean that the Big Bang is a nexus, the starting point from which timelines extend in all directions? If I could travel back in time past the Big Bang, would I find myself moving forward in another reality opposite our own? Is time actually a closed loop, a great ouroboros, with the Big Bang at its beginning and ending? Lastly, why is Time just a magazine and not also a game and cereal like Life?
Bookies are for rookies…I go where the real money is at: Brokers!
Sorry about that whole tech bubble thing.
I like to think that time travel is possible and there’s a theoretically perfect time machine, much like the theoretically perfect engine where all energy is converted into motion. Anyway for this perfect machine time travel is an extremely complex and difficult process. So difficult in fact that if you were to travel 1,000 years back in time it would take the machine exactly 1,000 years to get you there. Of course taking 1,000 years to get 1,000 years into the past puts you 1,000 years ahead of 1,000 years ago and right smack dab where you left in the first place that the exact moment you left. To an outside observer it would appear as though both you and your machine suddenly aged 1,000 years. Meaning suddenly you’re not doing so well.
Of course realistic time machine can’t match that efficiency and so might take 1,100 years. It also works that way for travel into the future. Still hiding out in the time stream would be a great way to hide from the cops till the heats blown over.
Okay, here’s what I’d do if I had access to a time machine.
-
I’d start saving pennies from the 40’s. I might even go to coin shops and buy old pennies, nickels and dimes that aren’t particularly valuable.
-
I’d go back in time to when the money was new or only slightly old and buy things that I knew would increase in value, but weren’t rare at the time. First issue comic books, old lunch boxes, trading cards, etc., but, I wouldn’t buy too many, because it would look suspicious on return and might also lower the value.
-
I’d get a long term rental on a safe deposit box, or secure the items somewhere that I knew I’d be able to get them later.
-
Return, claim the items and sell them at auction.