Bitcoin neared $50,000 for the first time on Tuesday, while the dollar declined and hesitant stock traders tracked an anticipated US fiscal stimulus and Covid vaccine developments.
Asia's main stock indices closed stronger, with Tokyo hitting a 30-year high, while the Dow Jones index was slightly softer in midday trading on Wall Street.
Bitcoin briefly pushed to a record-high of $48,215.83 after winning a huge boost Monday from news that Elon Musk's Tesla had invested $1.5 billion in the cryptocurrency.
It later eased back to a level near $47,000.
Stocks were helped a bit by expectations of a strong economic rebound once vaccination programmes make more headway, but the optimism was curtailed by delays to a potentially huge US stimulus plan.
And President Joe Biden's $1.9 trillion rescue bill is now also fuelling global inflation worries, alongside rising oil prices and the prospect of large consumer spending post-lockdowns.
"The real elephant in the room is what happens if oil prices continue to rise at their current rate," noted Michael Hewson, chief market analyst at CMC Markets UK.
Benchmark crude contract Brent North Sea held around 13-month highs above $60 on Tuesday thanks to surging demand expectations as economies reopen.
"Oil's fundamentals are looking strong again on both (the) supply and demand side," said Edward Moya, analyst at Oanda trading group.
"Despite demand being down about five million barrels year-over-year, optimism is high that vaccine rollouts will have key parts of the global economy return to normal."
Axi strategist Stephen Innes said the inoculation drive "provides the ultimate recovery safety net that will allow people to participate on all those pre-Covid activities like the simple pleasures of going to a movie or having a meal out".
In another sign of more upbeat times, crisis-hit Japanese carmaker Nissan upgraded its full-year forecast again as the global auto industry shows signs of recovery from the coronavirus pandemic.
- Key figures around 1645 GMT -
New York - Dow: DOWN less than 0.1 percent at 31,362.69 points
EURO STOXX 50: DOWN 0.2 percent at 3,658.97
London - FTSE 100: UP 0.1 percent at 6,531.56 (close)
Frankfurt - DAX 30: DOWN 0.4 percent at 14,006.22 (close)
Paris - CAC 40: UP 0.1 percent at 5,691.54 (close)
Tokyo - Nikkei 225: UP 0.4 percent at 29,505.93 (close)
Hong Kong - Hang Seng: UP 0.5 percent at 29,476.19 (close)
Shanghai - Composite: UP 2.0 percent at 3,603.49 (close)
Pound/dollar: UP at $1.3794 from $1.3741 at 2150 GMT
Euro/dollar: UP at $1.2102 from $1.2049
Euro/pound: UP at 87.73 pence from 87.67 pence
Dollar/yen: DOWN at 104.61 yen from 105.22 yen
Brent North Sea crude: UP 0.5 percent at $60.86 per barrel
West Texas Intermediate: UP 0.2 percent at $58.09 per barrel