After a nightmarish day yesterday, stock markets opened today with more red ink.
Thursday's big problem was a 7% slide in CitiGroup stock on Wall Street, prompted by fears that America's biggest bank would need to raise more capital to cover losses in the sub-prime mortgage market.
Hitherto the received wisdom has been that the banking giants were doing well enough from their other businesses to cover mortgage shortfalls but Merrill Lynch's $7.5bn write-down put an end to that.
London fell sharply too, with Barclays the hardest hit, and opened weaker this morning although a few "value" buyers were nibbling.
Overnight, markets across Asia fell for the second day and all eyes will be on Wall Street when it opens at lunchtime UK time.
The falls reversed Wednesday's gains after the US Federal Reserve cut interest rates by a quarter point to 4.5%. The small print of the announcement made clear that this was as far as the Fed wants to go because it's still worried about inflation, spurred by an oil price approaching $100 a barrel.
So what are the banks to do?
If they can't unload the billions of dollars of mortgage debt on their books they'll need to widen the spread between what they charge borrowers and pay depositors.
This will put the screws on consumer spending and company investment, making a recession in the US (and indeed the world) more likely.
In London, The Bank of England sources are making it pretty clear that inflation fears will prevent it from lowering interest rates any time soon.
It also has problems of its own of course, chiefly the £23bn it lent to mortgage bank Northern Rock (that's several hundred pounds for each of us).
Its decision not to pump liquidity into the whole banking market when the first credit crisis broke in August is looking worse by the hour.
That might have got Northern Rock off the hook without too may people knowing about its troubles, and other lenders may have helped it out.
Is there any light in this particular tunnel?
Well, markets seem to have short memories these days (which isn't wholly a good thing, of course) and confidence might return to the markets.
Outside the financial sector earnings are still strong, but that's the logical view. And fear tends to trump logic at times like these.
And the outlook for marketing budgets?
Things may turn by the end of the year when many such decisions are taken. But if your clients are setting them now, it's belt-tightening time.
Stephen Foster is a former news editor of ±±¾©Èü³µpk10, former editor of Marketing Week and Evening Standard ad columnist. He is a partner in Editorial Partnership and writes the blog and Politics of the Media for Brand Republic.