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Twitter Inc. (NYSE: TWTR) became a legal short sell this week. That should include the caveat of whether your brokerage firm could even find shares to borrow. One trader told us he was given a cost of borrowing at 10% to 15% for only a very small number of shares. Now we have another way of getting Twitter exposure: stock options, puts and calls, make their debut on Friday.

We would warn any new investors and traders that the option prices on Twitter likely will be volatile and also will be very highly priced. The implied volatility could even be off to the point that the options look and feel mispriced, but we have to wait for the dust to settle to make that call. Many new traders will choose to get exposure in the options for upside or downside, and we have not yet seen how much they will have to pay.

The volume of the options contracts could easily exceed 100,000, depending on the strike prices, expiration months allowed and of course the premium per contract. With each contract representing 100 shares, keep in mind that each 10,000 options contracts that trade is the equivalent of 1,000,000 shares of common stock on a fully leveraged basis.

Thursday’s trading volume was just over 11 million shares in the stock, but Wednesday saw almost 8.7 million shares traded and Tuesday’s volume was closer to 6.3 million shares.

Twitter shares traded lower mid-week but are back up at $44.69, and that compares to a close of $44.90 on the first trading day.