Following on from my post about listed private equity (LPE), the LPX50 is an index that is commonly referred to in the LPE industry. From the LPX website:

The LPX50 is a global index that consists of the 50 largest liquid LPE companies covered by LPX.

The LPX50 has been absolutely smashed over the past year or so. Some attribute this to the public nature of LPE, some attribute it to the state of all private equity, and some attribute it to the size of these funds (and hence relating the LPX50 performance to that of mega-buyout funds). Either way, you could do a lot worse than buying the LPX50 right now (such as buying it in mid-2007).