I have categorized the entries into broad heads as it will be easy to browse through the recipes. Hold your breath as here comes the roundup…
Here’s a peek into what a perfect Tamil meal looks like.
Sharmi from Neivedyam has come up with a whole spread that signifies the Tamil Cuisine.

Tiffin
Arisi Upma from Menu Today

Sevai upma - Trupti from The spice who loved me
Upma made by Sajeda of Chachis kitchen

Venpongal from Swapna of Susarlas kitchen

Temple style tamarind rice - Usha from Samayal Ulagam

Masal for masala dosa from Mythreyee of Try This Recipe
Hot pongal and kadalai paruppu chutney from Deepa of Recipesnmore
Lentil donuts in lentil soup vada - Padmaja from Spicy Andhra

Oothappam from Suma of Veggie Platter 
Lemon Sevai from LakshmiK of Veggie Cuisine
Spinach uttapam - Coffee from the The Spice Cafe 
Tamraind rice - Swapna from Swad of India 
Thayir vadai - Priya from Priya's Kitchen
Rawa dosa - Richa from As Dear As Salt 
Rawa idli from Mommy friendly recipes
Elumichampazha sadam - Aarti from Aartis corner 
Venpongal and Sambar - Sreedevi from Sreelu's tasty travels
Snacks
Murukku - Prema from My Cookbook
Javarsi Vadam - Deepa from Recipesnmore

Yelai vadam - Hema from Vegconcoctions

Rasam
Takkali Rasam - Sharmi from Neivedyam
Paruppu rasam - Jas from Just for fun

Rasam - Kajal from Kajal Dreams 
Neem flower rasam - Suganya from Tasty Palettes
Tomato rasam - Coffee from The spice cafe 
Spicy rasam - Reena from Spices of Kerala
Vepampoo rasam - Sneha from Kadambam
Podis and chutneys
Paruppu thuvaiyal - Viji from Vcuisine
Paruppu podi - - Sharmi from Neivedyam
Karuvepillaipodi - Revathi from En Ulagam 
Rasam powder - Coffee from The spice cafe 
Sambar
Arachu vitta sambar - Sheela from Delectable Victuals

Vendakkai sambar - Sharmi from Neivedyam
Sambar - Coffee from The spice cafe

Kootu
Beans kootu - Viji from Vcuisine
Kootu - Bee from Jugalbandi
Pudalangai molagootal - Roopa from Recipe of Choice 
Keerai poritha molagootal - Sapna from Indian Monsoon
Sorakkai pal kootu - Sharmi from Neivedyam
Peerakangai kootu - Pavani from Cooks Hideout 
Kosu kootu - Lakshmiammal from Cook Food Serve Love 
Kuzhambu
Milagu kuzhambu - Viji from Vcuisine
Vatral Kuzhambu - Ayesha from Vivakaarasamayal 
Chithambara Kothsu from Menu Today
Morkozhambu - Prema from My cookbook
Thalaga kozhambu - Kanchana from Married to a desi

Poondu kozhambu - Pearlin from Purl up and Crochet

Murungakai vathakozhambu - Ranjani from Eat and talk 
Mor kozhambu - Bharathy from Spicy Chilly 
Vatral kozhambu - Santhi from Me and my food thoughts 
Vatral Kozhambu - Nupur from One hot stove 
Celery kuzhambu - Bhagyashree from Crazy Curry 
Thakkali kurma - Revathi from En Ulagam 
Poriyal (dry curries)
Chettinadu style uppu kari - Sigma from Live to eat 
Potato in Tambram cuisine - Nandita from Saffron Trail 
Raw banana vegetable - Manasi from A cook at heart
Green peas with lovage seeds - Swapna from Swad of India
Keerai as a side dish - Pooja of Creative Pooja

Other curries
Ennai Kathirikai - Sharmi from Neivedyam
Vadakari - Jas from Just for fun

Keerai masiyal - Pearlin from Purl up and Crochet

Keerai masiyal - Nandita from Saffron Trail

Payatham parrupu masial - Deepika from Ammalus kitchen
Non-vegetarian
Chettinad chicken curry - Sailaja from Sailu's food
Mutton biryani - Maheshwari from Beyond the usual

Sweets/Desserts
Asoga - Priya from Live to cook

Rava kesari - Sharmi from Neivedyam
Sweet pongal - Asha from Foodies Hope
Adhirasam - Prema from My cookbookMiscellaneous
Neer Moru - Sharmi from Neivedyam
Spiced buttermilk - Swapna from Swad of India
Check out an online index of blogged tamil dishes at Tamil Cuisine started by Revathi and Prema Sundar.
The more the merrier. Also check out the Tambram Recipes at Nandita's blog - The Saffron Trail.