I used five gallon buckets, in pairs, but this would work with any number. They are very easy to clean, and eggs gently roll right to the back for collection. Just make the 2x4s longer and you could do a row however long you like.
1. Remove one half of the bottom of the bucket. This will be the back of your box where you pick up eggs, open half end up. A Sawzall will do it.
2. Set two 2x4s about 10 inches apart, and set 10 inch 2x4s (or scrap lumber that will fit) across every 15 inches or so (width of rim of bucket plus 2 inches-ish), so it looks like a ladder. Make as many spaces between rungs as you have buckets.
3. Place buckets on their sides onto long 2x4s between 'rungs'. Space everything evenly.
4. Make sure the ladder rungs and the fronts of the buckets are even. Nail rungs. You may need to move buckets out while doing this, depending on how close you put the buckets.
5. Make sure the opening in the bottom of the bucket is at the top. Nail through side of bucket into long 2x4s. Nail from inside the bucket.
6. Nail 1x6 (or whatever you have that will work) across bottom of fronts of buckets, nailing into the rungs. One 1x6 can do the whole row if you have one long enough.
These might be a bit small for really big hens, but your average hen or bantam would be fine.