To buy 1000 contracts here is the cost
$0.10(cost of contract)x1000(number of contracts)x100(number of shares
each contract controls)=$10000

profit= $17.53x1000x100=$1,753,000 nice $:)$

Not 1000 contracts for $100 dollars as you stated, 1000 contracts for
$10,000.
After today these contracts are worthless cause they expire,
To trade options you need to open a margin account.
Options are very risky and you should not use money that you cannot
afford to loose, same with stocks.
Seen many posts on here where students used there college money to buy
stocks(bear sterns) and loss their ass. If you are buying something
with a good chance of going down alot(high risk) it is always good to
buy a put(hedge) in case the stock drops big time then you can always
sell your stock at the strike price of the contract on the date it
expires. One can hold both a call and a put on  a stock at the same
time, also known as a straggle when the strike price and month expiry
is the same. A different strategy is a strangle ie current stock price
is $20 and one buys one may 17.5 put and one may 22.5 call(good
strategy when you expect stock to swing big one way or another)

The Strike Price (or Exercise Price) is price the underlying security
can be bought or sold for as detailed in the option contract. You
identify options by the month they expire, whether they are a put or
call option, and the strike price.

Call Option: An agreement that gives an investor the right (but not
the obligation) to buy a stock, bond, commodity, or other instrument
at a specified price within a specific time period. (Investopedia.com)

Put Option: An option contract giving the owner the right, but not the
obligation, to sell a specified amount of an underlying security at a
specified price within a specified time. This is the opposite of a
call option, which gives the holder the right to buy shares.
(Investopedia.com)

Hope this helps you understand options a bit better :)