What's better than momentum? Mo' momentum. Let's take a closer look at five of this past week's biggest scorchers.

Company

April 5

Weekly Gain

BGC Partners (NASDAQ:BGCP)

$5.62

35%

Astex Pharmaceuticals (NASDAQ:ASTX)

$5.39

21%

Niska Gas Storage (NYSE:NKA)

$15.51

20%

Best Buy (NYSE:BBY)

$25.45

15%

MagicJack VocalTec (NASDAQ:CALL)

$15.68

12%

Source: Barron's.

Let's start with BGC Partners. The brokerage provider servicing the wholesale financial and real estate markets soared after agreeing to sell its electronic Treasury trading platform to Nasdaq OMX Group. The deal is initially worth $750 million in cash, but it could be worth as much as $1.23 billion over the next 15 years if additional earn-out bonuses get shelled out. BGC Partners began the week valued for less than the value of the deal for its subsidiary.

Astex Pharmaceuticals moved higher after RBC Capital Markets initiated coverage on the cancer-tackling biotech. RBC established an "outperform" rating and a $9 price target on the stock. That's an impressive goal when you consider that Astex shares began the year trading below $3.

Niska Gas Storage Partners popped after the operator of three natural gas storage facilities across North America announced an equity restructuring that eliminates its subordinated units. Wall Street clearly liked the makeover, as analysts at Wells Fargo and Barclays upgraded the limited partnership on the news.

Best Buy lived up to its name when the stock soared after announcing an impressive marketing deal with Samsung. South Korea's electronics giant will open small stores within the retailer's cavernous superstores to showcase and sell its smartphones, tablets, and laptops.

magicJack VocalTec made a winning call after posting better-than-expected financial results. The telephony pioneer is making some serious inroads with the growing popularity of its magicJack Web-based phone service. This past week's quarterly performance capped off a fiscal year that, according to Bloomberg, delivered the company's first annual operating profit since 1996.

Longtime Fool contributor Rick Munarriz and The Motley Fool have no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.