Check the newsgroups and try to determine some frequent problems and cover them here. Again an example from the Multi Disk HOWTO.
This is just a collection of what I believe are the most common questions people might have. Give me more feedback and I will turn this section into a proper FAQ.
Q:How many physical disk drives (spindles) does a Linux system need?
A: Linux can run just fine on one drive (spindle). Having enough RAM (around 32 MB, and up to 64 MB) to support swapping is a better price/performance choice than getting a second disk. (E)IDE disk is usually cheaper (but a little slower) than SCSI.
Q: Are there any disadvantages in this scheme?
A: There is only a minor snag: if even a single partition overflows the system might stop working properly. The severity depends of course on what partition is affected. Still this is not hard to monitor, the command df gives you a good overview of the situation. Also check the swap partition(s) using free to make sure you are not about to run out of virtual memory.
Q: OK, so should I split the system into as many partitions as possible for a single drive?
A: No, there are several disadvantages to that. First of all maintenance becomes needlessly complex and you gain very little in this. In fact if your partitions are too big you will seek across larger areas than needed. This is a balance and dependent on the number of physical drives you have.