Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of drilling technologist Tesco Corp. (Nasdaq: TESO) look like black gold themselves today, shooting up as much as 10% to set 52-week highs on heavy trading volume.

So what: Tesco got some love from Standard & Poor's analysts today: The stock was already rated a "strong buy" by that firm, but received a "stock of the week" gold star and a video review to boot. For a lightly traded small-cap like Tesco, that's often all it takes to send the stock on a rocket ride -- or a plunge.

Now what: Partly thanks to today's boost, Tesco is on an absolute tear. The stock has gained 84% over the past year and 41% in the past month. S&P lauded the company for solid cash flows, strong innovation, and a debt-free balance sheet, and thinks the company could be a buyout target thanks to these qualities. Our CAPS investors might agree, as Tesco vacillates between a respectable four-star rating and a tip-top five stars these days.

Interested in more info on Tesco? Add it to your watchlist.

Fool contributor Anders Bylund holds no position in any of the companies discussed here. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool is investors writing for investors.