[ADRIANFR]

This is very unlikely to happen because: 1. When a startup sells shares (i.e., you purchase stock) it sells them not only for money, but also for advice and connections. Most of the time these are more valuable than the cash. Since you are likely (only) an engineer/geek, your part of the deal is short. 2. Even if they would want your money, evaluating a startup's worth (for pricing your shares)is extremely difficult and/or expensive. So the won't go through this process for a few thousand dollars.

[johnrob]

Everything has a price. If the seller doesn't want to sell, it just means the price is too low.

[ADRIANFR]

Technically you are right, everything has a price. Except when that price is way too high. So if you think a share is worth between say, $5 and $10, they can either say (nicely) "we're not selling shares right now", or say (rightly and rudely) "we can only sell YOU shares for $1000/share". And that may really be a fair price from their point of view, since having you (a nobody in the VC world) as an investor is really detrimental to their image.