John Sneed at Ministerial Meanderings provides a good (and much better, imho, than Phil Johnson's) definition of hyper-calvinism in a recent re-post (link). Also important is his post's emphasis on the need to be Biblical Christians, recalling that for us the Scripture is not just a rule of faith, but the rule of faith.
UPDATE: Mr. Sneed mentions the "love of God for the non-elect" issue that is sometimes brought into the hyper-Calvinism discussion, normally without warrant. He doesn't really make that his definition (that I could see) and I didn't think it worthwhile mentioning that minor issue in his post. That said, plainly the two major points of his definition:
1) Teaching that God attains ends without means; and
2) Teaching that there is no need for evangelism,
hit two of the three main areas of hypercalvinism.
A third area would be teaching providence-favoring incompatibilism: the error of asserting that moral choice and divine Providence are incompatible, accepting Providence and consequently denying moral responsibility.
There are several things that are not properly classified as hypercalvinism:
1) Scrupling over words such as:
a) "Offer" of the Gospel (as long as one proclaims the gospel, refusal to use the word "offer" may make one unconfessional, but it does not make one an heretic);
b) "Common grace" (as long as one proclaims that God's providential dealings extend to both the elect and reprobate, one is not a heretic simply because one refuses to use the term "grace" for things other than saving grace);
c) "love of the reprobate" (there is no rule that says people have to use the adjective "love" to describe God's relationship toward those to whom he may give riches in this life but hell forever); and
d) "duty faith" (as long as one does not deny that faith is commanded by God, refusal to use the expression "duty faith" cannot be considered heretical).
2) Denying that non-Calvinists are unsaved. This is a rather extreme view, no doubt, but it is not what hyper-Calvinism is.
3) Being a big meanie. Remarkably, in some circles, I've seen this used. Don't be a big meanie, but if you are one, that doesn't make you a hyper-calvinist.