Ebuyer are doing a similar deal on a PS3 - which is worth more than a Wii +Wii fit at £299. Still a good deal though. http://www.ebuyermobile.com/paymonthly/t-mobile/combi_30/nokia/3109/564579.html Envirofone will give you £12 for the phone as well - If you don't want to ebay.
Dunno whether it's a good deal or not but I can vouch for the free gift. colleague of mine got his ps3 within 5 days of sending back his voucher.
The following is taken from the ]BuyMobilePhones.net terms & conditions. 16.4. New customers of buymobilephones.net can now claim their electrical free gift in the following ways: 1. You can now claim your electronic free gift as soon as you receive your mobile phone. Your phone package will include a claim voucher. All you need to do is return the claim form with one acceptable proof of address and one acceptable proof of signature. A list of acceptable proofs of address and proofs of signature is available at ]buymobilephones.net/free_gift_claims_new.ihtml. This must be sent within 90 days of the date of the connection of your mobile phone. Subject to stock availability we will then send your electronic free gift out within 7 days. 2. or if you have difficulty finding the correct proofs of signature or address you can claim your electronic free gift by sending us clear, legible photocopies of your first two bills within 90 days of the date of the second bill. Bills received after this date will not qualify for their gift. Bills must show no outstanding money from previous bill and also show no changes to your tariff (e.g. T Mobile Flext 35 changed to T Mobile Flext 30). Please do not send original bills; items sent to us cannot be returned. 3. You can pay a refundable deposit and receive your free gift with your mobile phone. You claim your deposit back by following our standard claims procedure; return your claim voucher and one acceptable proof of address and one acceptable proof of signature to us within 90 days of the date of the connection of your mobile phone. On acceptance of your claim we will refund the money to the credit or debit card with which you ordered. It may take up to 7 working days for the refunded money to be available in your account. 16.4b. Existing Customers of buymobilephones.net can now qualify for instant electronic free gifts. If you are an existing customer of buymobilephones.net and meet the following conditions then subject to stock availability we will send your free gift out with your phone. You must have been an existing customer of buymobilephones.net for at least 6 months and have no outstanding airtime debts (unpaid bills) and must not have changed your tariff down from the original tariff ordered from this site. Customers must provide proof of original purchase by providing us with either their original order number or sale receipt number. Your free gift will then be sent out with your handset unless there is a stock shortage. If there is a stock shortage we will inform you at the time of your order of the anticipated delivery date. 16.4c. Any cash offered in addition to electrical Free Gifts will be automatically paid via BACS in to the bank account supplied at the time of ordering, after a period of 30 days after dispatch of your Free Gift.