I don't have any accessories for my V35 yet. If you're thinking of the keyboard, you may want to get the Pocketop infra-red keyboard, which costs a bit less than the Viewsonic one, and can be used with most PDA's out there for when you upgrade in the future. The only downside is that it probably drains the V35 battery quicker as it uses IR.
What we need is a really good after-market case. The Cover-up from
www.thepocketsolution.com seems interesting, but it doesn't provide complete protection. The battery extender they sell, too, might come in handy, but I think it is overpriced.