XMR is a proud member of top20 cryptocurrencies Index http://Coinoindex.com, which can be traded at https://poloniex.com/exchange#btc_index exchange now.

http://coinoindex.com

Monero is part of the top20 altcoin index: Link Text, The index includes the top 20 alternative cryptocurrencies with the largest market capitalization and tracks the value of the portfolio (in BTC), in which each coin has a 5% share. The index was created to be an analogue of Dow-Jones or S&P indexes for the altcoins arena.

Rules of index composition: - Coin should be traded on at least three exchanges, with cumulative daily volume above $1,000 for the last 14 days - Coins that track a value of a certain asset (USD, CNY etc) cannot be included. - Each coin included in the portfolio is given the same weight.

You can invest in the index by using the NXT Asset Exchange, NXT Asset ID 13634675574519917918 (Link Text). The asset tracks the index value, and constant buy/sell liquidity is maintained. You can invest using NXT cryptocurrency (you can exchange BTC to NXT directly in the NXT client from Link Text or at Link Text or BTC at Link Text