Assuming there is no contract or regulation requiring you to work your notice period, the main repercussion of resigning without notice is that is is extremely unprofessional. It will be noted by coworkers and managers as a significant problem with you. It will be mentioned if a future employer calls for a reference, and will be mentioned informally in networking by those coworkers and managers. That company will not rehire you and it will be seen as a big black mark by future employers who find out.
If you don’t plan to use this company as a reference and don’t plan to work with any of these people again or people they talk with, then there will not be any external drawback, just the damage you do yourself by teaching yourself to behave unprofessionally.