AMD and nVidia may well have the monopoly on add-in graphics cards for those needing performance in render-intensive programs such as games or design software (such as AutoCAD or 3D Studio Max), but if your after a low-profile, or low-power solution Matrox may offer a better option.
With the P690 series of cards, Matrox is offering a range of PCI and PCI Express cards, including one intended for a x1 PCI Express slot. Obviously this means it can be using in x1, x4, x8 and x16 slots, so if you happen to have a few RAID cards, for example, installed you can still be able to get a dedicated card.
Also catching my eye are the PCI and x16 PCI Express P690 Plus cards. Both cards are capable of running two digital monitors, which isn't anything out of the ordinary. However, using a separate cable (which will set you back £50) you can up that to four analogue monitors. Even cooler, if you use two of the cards, you can have up to four digital, or eight analogue monitors running off one system. A perfect solution for that evil genius lair you were planning.
Also noteworthy is the power drain, or lack thereof, at 12W on the P690 Plus and a tiny 10W on the bog-standard P690. And, better still, all the cards are passively cooled, again ideal for the environment the cards are intended. Pricing is between £100 for 128MB, single DVI-port cards, going up to £145 for the 256MB Plus options. While there are cheaper solutions available, the level of flexibility Matrox's latest cards offer is undeniable.