In this day of impersonal electronic correspondence the old fashioned letter carries serious weight (literally) and that's why it's making a comeback. When you can jot off a quick email or instant message (in some kind of crazy shorthand) and send it off at the speed of light, while the message is received intact, something is lost in all those 1s and 0s. And that something is authenticity. There's something about the act of putting ink to paper and the receipt of a physical letter that brings a level of personal experience to the communication that is simply not available via electronic means. So when you've got something to say (especially to someone special including family members, friends and co-workers) and you don't require an immediate response, bust out that writing quill and stationary and say it like you mean it, in writing.
Be the Paper
Ok, this may seem a little obvious, but the whole point of personalized stationery is to make it personalized. So give some serious thought to this. Your stationery should say something about yourself, think of it as your brand - when someone opens a letter or receives a note from you the first thing they're going to notice is the design elements on the stationery, what's the message you want to convey here? Just as important as the design elements (e.g. your name, an insignia, etc) is the font and paper type and color. These combined elements create a paper reflection of you - what do you want to look like?
If One is Good, Two is Better
Personalized stationery is great, but what if your stationery doesn't really fit the occasion? Say you just interviewed for your dream job and you want to send a thank you note to your would be boss (which is a must - send a thank you email later that day, but follow that up with an actual physical thank you note), but your personalized stationery has a Martini glass or some other fun, whimsical design on it - this may or may not be (depends on your "boss") the type of message you'd like to send to this person. Ah, but if you had 2 types of personalized stationery , one formal (appropriate for would be bosses, co-workers, grand parents, etc) and one informal (appropriate for friends, lovers, ex-lovers, etc) then the problem is averted.
Spell It Properly
If you got here by searching for "stationary", you might be better off standing still.