What language is on the server? Just html or do you have perl, PHP, java, etc.? If it's just html, well, it will be a little sticky but do-able.
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I would have two forms, if you had the ability to do html alone; or else I would automatically email it, and permit whoever gets it to optionally discard it.

Here's the rough scheme:
Code:
<form method="post" action="mailto:[email protected]">
Name: <input type="text" size="10" maxlength="40" name="name"> 

Input: <input type="input" size="10" maxlength="10" name="input">
</form>
Be sure to affect the maxlength depending on the input type