Hot Stocks You're Buying Now

Welcome back to another Foolish review of the hottest stocks as ranked by Motley Fool CAPS. We're looking at the three best-performing industries over the past 30 days and your favorite long and short candidates in each.

How much difference can a week make? Not much, apparently. Travel services firms such as priceline.com (Nasdaq: PCLN) are still gaining altitude, up 56.8% as a group over the past 30 days. But even they fell short of the heights achieved by diagnostic substances manufacturers, whose 64.4% average return scorched everyone to retain this week's top spot.

This week's third-place finisher is an old favorite. Solar power providers, such as SunPower (Nasdaq: SPWR) and budding tweener Yingli Green Energy (NYSE: YGE), are up 33.7% as a group since late March.

According to you, our Foolish readers, the best stocks in these industries to own now -- i.e., those with four or five of the maximum five stars in CAPS -- are:

And your favorite short candidates -- i.e., those rated with one or two stars in CAPS -- are:

My favorite stock among today's contenders is Amtech Systems, a supplier of equipment for manufacturing solar cells and related devices. CAPS investor pre176 best explained why in December, I think:

If everyone is at war, what better business is there than being an arms dealer? That's why Amtech is in such a good spot right now, all the solar companies are fighting tooth and nail to increase production dramatically. The proof is in the pudding for Amtech, with solar sales up 150% [year over year], and that doesn't include the $17.4 million that they just booked in one order ... nearly matching the previous year's solar income!

Nor does it include the $5 million in follow-on orders that Amtech announced on March 31. But is this really a cheap stock? A 0.59 PEG ratio based on calendar 2008 earnings estimates screams "yes!"

So does Fool EPS100Momentum, who suggested in a response to pre176's pitch that Amtech's intrinsic value is north of $69 per share. I'm not at all sure that's reasonable. Still, even if he were off by 75%, investors who buy now would realize a gain of at least 40%.

But that's my take. What would you do? Would you buy Amtech at today's prices? Let us know what you think by signing up for CAPS today. It's 100% free to participate.

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