Just as Black Friday has crept into Thanksgiving evening, Cyber Monday was already under way well before the stroke of midnight.

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Early Sunday, Toys "R" Us kicked off a week of online savings. Amazon wasted no time and started on Saturday. They're not alone — many major retailers were offering deals before the weekend was out, though some will offer even more late Sunday or starting Monday.

The upside: Consumers can still get decent savings without having to fight for a parking spot or wait 30 minutes on a checkout line.

Here are the Cyber Monday online hubs or sale info for some major companies, and some of the best deals we've seen active or upcoming so far:

Deals are already active, but several more will vary through the week:
iRobot Roomba 780 Vacuum Cleaning Robot for Pets and Allergies for $369
A 28-inch (off-brand) 720p Smart TV with Roku for $169. (A $32-inch model is available for $199 and a 1080p $40-inch model is $299)
• Other TVs start as low as $89
Assorted savings on TVs from major brands

Best Buy
Up to $100 off on iPad mini models (sale is active on Sunday, Nov. 29; it's unclear whether it will be renewed on Monday)
Toshiba - Satellite Radius 14-inch Touch-Screen Laptop, Intel Core i3 , 6GB Memory, 500GB Hard Drive for $449 (sale is active on Sunday, Nov. 29; it's unclear whether it will be renewed on Monday)

Discounts, on dresses, tops, pants, shots, bags, hats, jackets and shoes

Up to 50 percent off Berkshire Christmas Trees
A 5-megapixel ACTIVEON camera (similar to a Go-Pro) for $89
Buy two, get one free on Barbie, Monster High, Mega Blocks, Hot Wheels and other lines.
Home electric fireplace for $199

Use promo code DEALSEEKER through Dec. 1 to get an extra 20 percent off of purchases
Use code COZYUP to get $10 off select styles of home merchandise on Sunday

P.C. Richard & Son
Up to 50 percent off on TVs, with free shipping
(The store's email subscribers will be notified first of deals as they start on Cyber Monday. P.C. richard says it will offer thousands of items on sale Monday in-store and online)

Up to $300 off on laptops and desktops
Up to $100 off on monitors
Up to $100 off on Samsung tablets

Target.com purchases will be 15 percent off on Cyber Monday with promo code CYBER15. Also, Special "e-doorbusters" include (some items are active as of Sunday):
• Xbox One 500GB Gears of War: Ultimate Edition Bundle, $299.99 (Reg. $349.99), plus free EA sports game and free 3-month Xbox Live subscription with purchases
• 50 percent off licensed kids’ cameras including Frozen and Teenage Mutant Ninja Turtles
• Cra-Z-Art Ultimate 4 in 1 Easel, $45 (Reg. $98.99)
• Swagway x1 Hands-Free Smart Hoverboard, $399 (Reg. $499)
• 48” Samsung 4K Ultra HD TV, $599.99 –Save $300 plus a free $100 Target GiftCard
Week-long deals are listed at Target.com/WeeklyAd.

Toys "R" Us
Specials beginning at 8 a.m. Sunday include:
50 percent off Thomas & Friends Wooden Railway Gold Mine Mountain Set (Was $159.99; Now $79.99)
Buy one, get one free WWE Battle Pack Series 2-packs
40 percent off each on FurReal Friends Pom Panda or Get Up and GoGo My Walkin’ Pup
Specials beginning on Monday include:
• $150 off Tonka 12-volt Dump Truck Ride-On (Was $349.99; Now $199.99)
• Up to $150 off on select Meccanoid robotics items
• Star Wars Legendary Jedi Master Yoda (the store says it will be offered for a "hot price," plus $30 off on select Star Wars Interactive figures
• $50 off for all Xbox One game systems (Was $349.99; Now $299.99)
• $95 for a Barbie Malibu Dream House ­(Was $134.99)
• 50 percent off all Playmation Starter Packs (Was $119.99; Now $59.99)
• 50 percent off You & Me So Many Babies (Was $19.99; Now $9.99)

Deals are already active:
50-inch Samsung TV for $497.99, down from $699.99
RCA Viking Pro 10.1-inch 2-in-1 tablet for $79
Dyson DC33 Multi-Floor Bagless Vacuum for $197, down from $269
Meccano Meccanoid G15 Robot for $129.99, down from $179.97
Fitbit Flex Wireless Activity Sleep Band for $59 to $79
• GoPro HERO4 Silver Edition Action Camcorder for $317.99 (must add to cart to see price, down from $399)

According to financial expert Jordan Goodman of MoneyAnswers.com, much of the post-Thanksgiving shopping is shifting from Friday in stores to Monday online.

"Because it's so convenient, because prices are so good, because selection is so good, I think Cyber Monday and online sales are going to continue to take market share from in-person sales for many years to come," Goodman said.

And Cyber Monday is turning into Cyber Week for many sites. Each day may offer different deals, or feature one specific major discount.

For the first time in its annual holiday shopping survey, the National Retail Federation asked consumers about their plans to shop on Cyber Monday. Nearly 80 percent said they may or definitely would. The NRF in October predicted that overall online sales for November and December would increase between 6 and 8 percent compared to last year.