You have 2 PCI-E cards, add 1 PCI card. Run two PCI-E cards in SLI. And PCI card will run the second monitor. Slow or not, its fast enough for a second monitor, and it works. Games will run in main monitor by default, there for it wont be slow.
In the second monitor you can have your messenger and internet open. Im sure PCI card can render a MSN messenger fast enough with out missing out on any important sybering. And they are faster then any on board video cards.