Just as we examine companies each week that may be rising past their fair value, we can also find companies potentially trading at bargain prices. While many investors would rather have nothing to do with companies tipping the scales at 52-week lows, I think it makes a lot of sense to determine whether the market has overreacted to the downside, just as we often do when the market reacts to the upside.

Here's a look at three fallen angels trading near their 52-week lows that could be worth buying.

You can't cure crazy
Earlier this month, shortly after biotechnology company Exelixis (EXEL 0.13%) won approval by the Food and Drug Administration for Cometriq to treat metastatic medullary thyroid cancer, or MTC, I exclaimed that investors must be on crazy pills for bidding down its share price. Three weeks later and I see the crazy-pill hysteria has spread even further. I feel now is the time to give Exelixis shares a good hard look!

I fully understand that there are only 2,250 cases of MTC diagnosed in the U.S. each year, so the market will be somewhat constrained for Cometriq, but the sheer dominance of the drug in trials should allow it to completely blow AstraZeneca's (AZN 0.28%) Caprelsa, which was approved last year for the treatment of MTC, right out of the water. Cometriq, in trials, demonstrated a progression-free survival rate nearly three times as long as the placebo, and a response rate of 28% compared to zero for the placebo! I feel very strongly that Exelixis will find additional indications for Cometriq and look forward to what could be a very robust growth period for the company. 

The light at the end of the tunnel
Three years ago you couldn't have given me free money and expected me to invest in any small-scale silver miners. Today, that's a completely different story and why I think all eyes should be closely watching Alexco Resource (AXU).

Alexco's most recent quarter, and many prior to that, show that it's successfully turned the corner of profitability and is now utilizing its mine byproducts and expansion to the fullest. In the third quarter, Alexco managed to increase silver production 12% as it boosted mined material in its mills by 11%, all while decreasing total cash costs by 33% at its Bellekeno mine over the previous quarter. With its margins improving despite relatively flat silver prices, I'm excited to see how rapidly profits will explode once it gets its Onek and Lucky Queen mines in operation over the next few years.

Based on its current forward P/E of 14, and my expectation that silver production will double by 2015, compounded with the fact that the Federal Reserve is printing money like a fiend and investors are still somewhat using silver as an inflationary hedge, I think Alexco will do just fine!

I'll gladly pay you Tuesday for an aircraft today
In the world of aircraft leasing, there aren't many public players: just Dutch-based AerCap Holdings (AER -0.63%) and Ireland-based FLY Leasing (FLY). AerCap, at nearly five times FLY's size, has cleaned up over the past year as FLY dug itself deeply into debt in order to expand its fleet and give AerCap at least a run for its money. Now, it looks like it could be FLY that's cleared for takeoff.

FLY's most recent quarter was marred by a one-time expense of $33.9 million tied to a long-term loan refinancing. Beyond this one-time cost, FLY's business looks ready to explode higher. As noted in the company's conference call, FLY is benefiting from airlines with older-generation planes that wish to utilize FLY's more fuel-efficient medium-age aircraft, and from newer fleets that simply don't have the capital to expand fully and want to rely on FLY's aircraft. In addition, the company's recent refinancing allowed its leverage ratio to drop from 5:1 to 4.2:1; now it won't have to refinance again until at least 2018. 

At just six times forward earnings, this places FLY at a slight discount to its peer AerCap and gives credence to my theory that this leasing company may have all the tools necessary for liftoff. Plus, FLY is yielding 7% and has paid out $5.24 in dividends over just the past 20 quarters!

Foolish roundup
This week's theme is all about patience paying off! Investors have been waiting for an FDA-approved drug from Exelixis, a margin expansion from Alexco, and a drop in leverage from FLY. With all of these ducks now in a row, all three look poised to head higher.

I'm so confident that these three names will bounce off their lows that I'm going to make a CAPScall of outperform on each one.