How do you search an amazon s3 bucket?

Just a note to add on here: it's now 3 years later, yet this post is top in Google when you type in "How to search an S3 Bucket."

Perhaps you're looking for something more complex, but if you landed here trying to figure out how to simply find an object (file) by it's title, it's crazy simple:

open the bucket, select "none" on the right hand side, and start typing in the file name.

http://docs.aws.amazon.com/AmazonS3/latest/UG/ListingObjectsinaBucket.html

Here's a short and ugly way to do search file names using the AWS CLI:

aws s3 ls s3://your-bucket --recursive | grep your-search | cut -c 32-