Rachel Adler, in chapter 5 of her Engendering Judaism, details a wedding ceremony meant to be a “lover’s contract,” based on shutafut, a traditional model for partnership (usually business partnerships) rather than the traditional model of marriage.
I don’t have the book handy–it’s in another country–so I’m not going to write about the ritual’s mechanics in detail. If someone does, feel free to email me; otherwise, anyone interested should just check the book for oneself.
It’s not clear to me whether a couple using her ceremony would be legally obligated as a business partnership (and what that might entail). I don’t know enough about hilchot shutafut to know how, halakhically, one might end a partnership. I suspect that there’s more than simply walking away, but this isn’t something I’ve studied in detail. Anyone who knows, please email me or comment here!
ADVANTAGES: Does not require a get, is fully egalitarian, is same-sex marriage friendly, has a historical connection to Jewish ritual history (ie, it’s not a ceremony invented whole-cloth). Is possibly binding legally.
DISADVANTAGES: It’s not kiddushin, so halakhically one is not fully married (I recognize that, re: the get issue, this is a plus for some people), it doesn’t “feel” like the traditional ceremony. Unclear (to the author of this site–I need to go learn this) what needs to hapen to “unbind” a partnership.