Marvel's Wolverine is one of, if not the most popular members of the X-Men ever to grace a comic book cover. The mutant's ability to heal from nearly any injury, along with his enhanced senses and standoffish attitude combined with his tragic backstory has endeared him to many a reader over the course of his nearly 50-year history. But in Ultimate X-Men #97, Professor Charles Xavier gets a chance to wield Wolverine's most iconic weapons: his claws.
Wolverine is known for his adamantium skeleton, but his nigh-unbreakable bones are not a part of his mutation. As part of Team X, Logan became a part of the Weapon X Program, which bonded his normal skeleton with the metal in a terribly painful and risky process. Not everyone could survive the procedure, but Wolverine's supercharged healing factor made him a perfect candidate. His claws, however, were always a part of his anatomy, but the claws are bones themselves. As part of Weapon X, they were sheathed in adamantium.
In the storyline of the Ultimate X-Men at the time, the mutant growth hormone Banshee enhances mutant abilities to dangerous new levels. The drug, however, is terribly addictive and some mutants can quickly become a danger to themselves and to others. Deep in the Savage Land fifteen years before the current timeline, Charles Xavier unsheathes his new claws and faces off against a velociraptor. In just a few panels, he kills the dinosaur and the raptor's body slams into the jungle floor. The drug is derived from Wolverine's DNA, granting Xavier not only his claws, but his senses and healing abilities too.
Xavier is amazed. Banshee provides power amplification, but "...completely new mutations. Unfortunately - it's completely unstable." Xavier, with his disciplined mind and powerful psychic mutant powers, was able to resist the addictive nature of the drug, but he fears others will not be as strong. Thus, Xavier decides to keep the nature of the drug completely secret. This includes wiping the memories of Wolverine and covering up Banshee completely. Unfortunately, judging by the current events in the Ultimate X-Men series, he wasn't entirely successful.
It must be noted that the Ultimate X-Men series is not technically set in the main 616 Marvel timeline, and some characters are quite different from their mainline counterparts. In particular, Xavier is more willing to toe the moral line in the Ultimate universe (though his 616 counterpart is not exactly Captain America himself). Nevertheless, seeing Professor X wield Wolverine's claws with wild abandon is certainly a new (and perhaps troubling) sight for X-Men fans.