Just Bento

I don't know how similar it is to crabstick, but we use tempeh in ours. I usually use the flavored strips called fakin' bacon and cut them into thinner strips. We like their flavor plus it's convenient, but you could also cut up ordinary tempeh and marinate it.

VegieWorld.com has a TON of vegetarian substitutes.

Vegetarian Crab Roll.

I just saw a post on kitteekake's blog where she fried tofu strips marinated in beet juice, sesame oil, soy sauce and rice vinegar to mock the appearance of crab stick. I thought it was clever. No instructions on the post, but one could probably play around, and it's a more nutritious alternative to the crab roll I linked to earlier.

EDIT: She DOES post the technique for pink tofu on a different site.

I don't know if it is made of veggies or other fishes, but in your grocer's Kosher section there might be fake crab sticks. My mom likes them.

Expanding on the tofu idea, have you tried yuba? (the skin that forms when making bean curd)

Perhaps one of the best ways of approximating crab sticks' surimi 'rubbery' texture might be the Chinese kind of yuba called tofu sticks or tofu bamboo (if you copy and paste 腐竹 and run it through Google Images you'll see lots of photos).

I do like the idea of cooked and shredded tempeh though.

And there's always seitan - which comes in so many varieties.
This isn't a route I would take myself, but there's a recipe here for making fake seafood out of seitan powder: http://www.vegan-food.net/recipe/1197/Seitan-Seafood-Scallops-Fish-Clams...
(although I might try using the cooking broth to flavour yuba sticks if I ever try and make vegetarian surimi)

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Kosher surimi/crab sticks are not vegetarian. Shellfish (crabs included) are prohibited from a Jewish diet so the fish paste used to make the sticks has to be free of non-kosher ingredients. It's quite normal for crab sticks to feature very little or any crab at all, the Kosher sticks just guarantee the exclusion of any shellfish.

"Imitation" crab meat is still fish IIRC, just whitefish instead of shellfish.

"Stop having the boring tuna; stop having the boring life" - Vince Offer

I don't know where you live, but here in the lower mainland of BC we have a supermarket chain called T&T and they carry a completely vegetarian crab stick. So they DO exist.