If there ever is to be a shock in a Grand Prix, it is likely to be in Monaco. The tight curves and (potential) rain means that an upset is always possible. Who can forget Panis in 1996? For this reason, I've placed 0.5 pts (in total), spread across the following drivers, all at 1000-1 (!) (on Betfair)
Jarno Trulli 1000 £2.00
David Coulthard 1000 £2.00
Heikki Kovalainen 1000 £2.00
Rubens Barrichello 980 £2.00
Jenson Button 1000 £2.00
Ralf Schumacher 1000 £3.72
Alexander Wurz 1000 £2.00
This is in addition to the Hamilton (F1) /Wheldon (Indy 5000) double at 16-1 I placed midweek.
If the rain doesn't come, I think the winner will come from Alonso/Hamilton. I'd make the betting a lot closer - Hamiltion at 5/2 is a fair bet. Alonso will probably lead to the first corner, but 4/6 is no value on him for Monaco. Hamilton could easily be carrying more fuel which could give him a critical edge in this race.
In addition, those laying Massa at 12/1 on Betfair could look at little red faced in 3hrs time.