Do you think you can spot a bargain in today's volatile stock markets? Do you have what it takes to match and outperform the top dealers in London, New York and Tokyo? Author and journalist Jonathan Maitland mortgaged his house and invested the proceeds to see if he could beat the market. But you don't have to go to those extremes.

The Irish Times and Goodbody Stockbrokers are giving you the chance to test your knowledge of the stock markets - and there's no need to sell the family home.

Our fantasy share competition, Sharetrack 100, will give you an imaginary purse of £1 million to invest and 100 shares to choose from. The rest is up to you.

An overall first prize of £15,000 (€19,000) will be awarded to the person whose portfolio has the highest balance at the end of the competition. Second prize will be £7,000 and third prize £3,000.

There will also be a weekly prize of £1,000 cash and one year's commission-free share dealing through Goodbody Stockbrokers for the contestant whose portfolio value has increased by the greatest percentage in that week.

Playing is simple. A contestant's portfolio must contain eight companies from eight different sectors. Between £100,000 and £200,000 can be invested in each company.

Two companies must be selected as core holdings, which are non-tradeable and must be held for the duration of the competition. Contestants can then select the remaining six from any other sector. They will get the opportunity to make one amendment to their portfolios each week.

But investors should remember that they are not investing for the long term when picking their stocks - just the three-month period of the competition. Stocks should be selected on the basis that they will do well over this period.

So if you think you can double your money, now is the time to enter. Even if you lose everything, maybe you can write a book about it. Mr Maitland did.