>>colone+(OP)
It is interesting to watch the effect of the Russian ruble collapse on Bitcoin markets... It is causing an influx of Bitcoin buyers on Russian exchanges: over the last 14 days, BTC is up +11% from 19000 RUB to 21000 RUB with most of the uptick happening in the last 24 hours (
https://bitcoinwisdom.com/markets/btce/btcrur) despite being down -13% from 380 to 330 USD on American markets (
https://bitcoinwisdom.com/markets/bitstamp/btcusd). There is an opportunity for arbitrage! The ruble is collapsing so fast that even buying at 21000 RUB is a steal (worth 310 USD as of Dec 16 21:00 UTC). And the collapse will likely continue in the next few days and weeks, so the arbitrage opportunity will grow bigger.
Edit: @potench preev.com is an inaccurate indicator of the BTC/RUB rate because it is basing its calculation "based on the USD Bitcoin price" per its footnote, so of course it will never show a big deviation from the BTC/USD rate. For the true rate you need to look at the real-time bid/ask spread on a BTC/RUB exchange such as btc-e.com which is why I linked to https://bitcoinwisdom.com/markets/btce/btcrur or you can also look at https://btc-e.com/exchange/btc_rur: bid/ask is 20855/21099 RUB as of 22:09 UTC, so the arbitrage opportunity is approximately 2000 RUB.