Let's have an English lesson. These are common errors that I see in my reading around the 'net--even in the work of (theoretically) professional writers!
Today, I'm going to mention two common errors in which people confuse homophones, perhaps because they've never actually seen the correct words (which, while they aren't particularly exotic, are also not incredibly common). There are a lot more than two, and some of them without the excuse of the words in question being mildly uncommon. I blame the popularity of phonetic spelling.
Let's start off with pique. The most common use of this word is as a noun, and I have not seen it misspelled in that context. However, pique can also be used as a verb, in which case it generally means "to stimulate". I almost always see "peek" or "peak" in cases where a writer clearly means pique in this sense. A reader with an extensive enough vocabulary to notice it will be pretty well thrown out of the story by an error like this. So, if you're writing and you're about to say someone's desire/curiosity/interest/(insert object here) has been peeked or peaked… don't. Someone's desire/interest/whatever can peak, but in that case you're saying it has reached its apex. I can't even think of a situation offhand where peek would make sense in relation to the sort of things that can be piqued.
The other word is eke. To eke is another verb. It has several related meanings: "to manage to support oneself or make a living with difficulty", "to make an amount or supply of something last longer by using or consuming it frugally", or "to obtain or create, but just barely". The word I most often see used in place of eke is "eek". "Eek" is a sound effect, not a verb.
Of course, the best thing to do while writing is keep a dictionary and thesaurus close at hand. Any time you have even the slightest bit of doubt about a word, look it up! I'll often stop and do this in the middle of a sentence (and I just use the dictionary & thesaurus on my computer, nothing fancy), but I know some people prefer to get it down on paper before getting down to the nitty gritty bits. If you don't want to interrupt your flow, I suggest putting a star or other mark next to words you're not entirely sure about so that you'll remember to check them out once you've got your first draft down. Whatever you do, take the time to make sure you're saying what you mean--after all, in writing, the right words are everything.
Bonus: Vile is not a noun. Vial, however, is.