If my ex was jacking off by himself, he would often freeze his loads for later. He shot huge loads and on days when he was off work and I had to work, he would jack off 3 to 5 times and have quite a collection. Usually he would shot his load into an ice cube tray. When he had 2 or 3 "sperm cubes" frozen, he would pop them into my ass before he fucked me.
But one time, I was gone for 10 days. During my time away, he shot his load into a ziploc bag and would freeze it in a long, thin shape. When I got home, he surprised me with a frozen sperm dildo he had made. It was about 7" long and maybe an 1.5 inches in diameter. He said he worked hard on it while I was gone. He then fucked me with it. While it was fun, it didn't work out very well. It melted too quickly and disintegrated inside my ass. But the experience was very hot!.