ACTIVITY in oil and gas companies has been going strong over the past few weeks, making a number of small and mid-caps ripe for a buy. Last week&rsquo;s announcement that Desire Petroleum has managed to secure a rig for drilling in the Falklands Islands, where up to 3bn barrels of oil and gas may be recoverable, saw shares jump from 61p to over 100p. Spread betters believe there are further gains to come, especially if the reserves prove to yield more than BG and BP&rsquo;s recent major finds. Spreadex has a December spread of 93.4p-96.2p.<br /><br />This news could prove critical for Desire&rsquo;s peer Falkland Oil &amp; Gas. Shares in Falkland Oil &amp; Gas have already rallied around 30 per cent in the last few days on speculation of what the future may hold, but a successful find for Desire in the new year could see its share price rocket. IG Index is currently quoting 133.7p-135.8p.<br /><br />Gold surged through the $1,000/oz level last week and there&rsquo;s no end of speculation about how high it will go. IG&rsquo;s current price for spot gold is $1,001.6-1,002.2. Gold miners like Hambledon Mining will benefit from the yellow metal&rsquo;s higher price. Its shares have gained some 50 per cent in the past couple of weeks and the scope for further gains here, given the potential for production to pick up combined with the higher yields, could bode well for the future. IG&rsquo;s&nbsp; Index price is 5.5p-6p.<br /><br />The retail sector was given a shake-up last week by Kraft&rsquo;s hostile bid for Cadbury, which saw shares in the confectionary firm jump 40 per cent. Despite the price falling from highs of 808p to around 780p by Friday, spread betters have been placing plenty of buy orders in expectation that further possible bids from Hershey's and Nestle could spark another rally. has a rolling Cadbury spread of 777.7p-779.8p.<br /><br />Department store Debenhams gives a trading update on Tuesday and investors will be looking to see how the retailer is doing in the current economic climate. The shares have performed well so far in 2009 &ndash; putting on a gain of 250 per cent since January &ndash; but for the past four months the share price has been moving sideways.&nbsp; Capital Spreads quotes a price of 84.4-85.0 for the rolling contract.