Billionaire hedge fund manager David Einhorn, who runs Greenlight Capital, just pitched his best ideas at the Robin Hood Investors Conference—one of the most stacked investing events of the year. It's closed to the media, but we have a source inside the conference. According to our source, Einhorn pitched SunEdison (SUNE) as a long. The solar power semi-conductor's stock has jumped about 5%, and has been the best performing solar stock of the year. According to our source, Einhorn said the stock's mispriced now. Einhorn also mentioned Terrform Power (TERP) as a long. That stock's up about 10% today. We're told that Einhorn also talked about Greece. He mentioned Alpha Bank and Piraeus Bank. Einhorn said get long with warrants, our source says. He said to short French debt. Here's a chart of SunEdison: Here's a chart of TerraForm: Join the conversation about this story »