As a testimony to the power of pop culture and music, especially in the past twenty years, a number of my favorite songs growing up were covers of old songs from years past. Of course there was the initial shock when I thought I was listening to freshly minted irreverence only to find out that my 80's rock goddesses had rehashed a 60's doo--oop--diddy! But I was hooked anyway because it worked, especially once I compared their upbeat rendition with the sullen, but equally mesmerizing original. They were both hits in their own right, fitting neatly into their respective eras.
The key to a successful cover is how it re--establishes the heart of what made the original a hit, and also takes a different direction along the way. Be it slower or faster, heavier or lighter, a twist on the chord structure, or it could even be a male singer opposed to female vocalist performing the original. The important factor is that there's something alluring yet different. Check release cover song
Sometimes the changes artists make to a cover can be so drastic that the best elements of the original song are lost and there's nothing coherently similar to bind the two together. The new version is unrecognizable. Not good, if the goal is to attract the listener who still hums the original and thus may be more accepting of the cover because it is instantly familiar. Too subtle a difference can also be a deterrent because the new version sounds too much like the original. Sorry, but it's the original we usually fall in love with, so unless there's a really good guitar solo tossed in as a distraction, we stick with what we know. Ultimately, the greatest service a cover does is pay homage to a well written song by simultaneously reminding older listeners as well as introducing younger generations in a manner that relates to them.
Having a well chosen and well performed cover song is an invaluable promotional tool for underground bands and indie musicians looking to target a particular demographic or reach a larger audience. A cover song has a good chance of being noticed amidst songs incorporating loops and samples from popular songs as the background for new compositions with altogether different lyrics and melodies.
When considering which song, or songs you'd like to cover, the best thing is not to dwell on what songs from your arsenal of oldies but goodies were the biggest hits. The songs that fit your style will actually present themselves to you. You may make a bigger statement remaking a song that wasn't necessarily a smash, but is still recognizable today. Your eventual choice will flow from you as if you've been performing it forever, and most likely, you have been, whether on stage, or in the shower. A good study lesson is American Idol. This offers excellent examples of right, and wrong song choices made by contestants. The perfect cover song should feel natural. The rest is up to fate, luck, and having a good producer is a definite plus.
If still unsure which songs would be good matches, or you want to find song title information, a great resource is the Harry Fox Agency at http://www.harryfox.com. This is a very expansive but easy to navigate database, and an industry standard for licensing copyrighted music. You can research, the writers, original performers, the publishers, etc.